diff --git a/datastructure/doublylink.go b/datastructure/doublylink.go
new file mode 100644
index 0000000..144ea55
--- /dev/null
+++ b/datastructure/doublylink.go
@@ -0,0 +1,228 @@
+package datastructure
+
+import (
+	"errors"
+	"fmt"
+)
+
+// DoublyLink is a linked list. Whose node has a generic Value, Pre pointer points to a previous node of the link, Next pointer points to a next node of the link.
+type DoublyLink[T any] struct {
+	Head   *LinkNode[T]
+	length int
+}
+
+// NewDoublyLink return *DoublyLink instance
+func NewDoublyLink[T any]() *DoublyLink[T] {
+	return &DoublyLink[T]{Head: nil}
+}
+
+// InsertAtHead insert value into doubly linklist at head index
+func (link *DoublyLink[T]) InsertAtHead(value T) {
+	newNode := NewLinkNode(value)
+	size := link.Size()
+
+	if size == 0 {
+		link.Head = newNode
+		link.length++
+		return
+	}
+
+	newNode.Next = link.Head
+	newNode.Pre = nil
+
+	link.Head.Pre = newNode
+	link.Head = newNode
+
+	link.length++
+}
+
+// InsertAtTail insert value into doubly linklist at tail index
+func (link *DoublyLink[T]) InsertAtTail(value T) {
+	current := link.Head
+	if current == nil {
+		link.InsertAtHead(value)
+		return
+	}
+
+	for current.Next != nil {
+		current = current.Next
+	}
+
+	newNode := NewLinkNode(value)
+	newNode.Next = nil
+	newNode.Pre = current
+	current.Next = newNode
+
+	link.length++
+}
+
+// InsertAt insert value into doubly linklist at index
+func (link *DoublyLink[T]) InsertAt(index int, value T) error {
+	size := link.length
+	if index < 0 || index > size {
+		return errors.New("param index should between 0 and the length of doubly link.")
+	}
+
+	if index == 0 {
+		link.InsertAtHead(value)
+		return nil
+	}
+
+	if index == size {
+		link.InsertAtTail(value)
+		return nil
+	}
+
+	i := 0
+	current := link.Head
+
+	for current != nil {
+		if i == index-1 {
+			newNode := NewLinkNode(value)
+			newNode.Next = current.Next
+			newNode.Pre = current
+
+			current.Next = newNode
+			link.length++
+
+			return nil
+		}
+		i++
+		current = current.Next
+	}
+
+	return errors.New("doubly link list no exist")
+}
+
+// DeleteAtHead delete value in doubly linklist at head index
+func (link *DoublyLink[T]) DeleteAtHead() error {
+	if link.Head == nil {
+		return errors.New("doubly link list no exist")
+	}
+	current := link.Head
+	link.Head = current.Next
+	link.Head.Pre = nil
+	link.length--
+
+	return nil
+}
+
+// DeleteAtTail delete value in doubly linklist at tail index
+func (link *DoublyLink[T]) DeleteAtTail() error {
+	if link.Head == nil {
+		return errors.New("doubly link list no exist")
+	}
+	current := link.Head
+	if current.Next == nil {
+		return link.DeleteAtHead()
+	}
+
+	for current.Next.Next != nil {
+		current = current.Next
+	}
+
+	current.Next = nil
+	link.length--
+	return nil
+}
+
+// DeleteAt delete value in doubly linklist at index
+func (link *DoublyLink[T]) DeleteAt(index int) error {
+	if link.Head == nil {
+		return errors.New("doubly link list no exist")
+	}
+	current := link.Head
+	if current.Next == nil || index == 0 {
+		return link.DeleteAtHead()
+	}
+
+	if index == link.length-1 {
+		return link.DeleteAtTail()
+	}
+
+	if index < 0 || index > link.length-1 {
+		return errors.New("param index should between 0 and link size -1.")
+	}
+
+	i := 0
+	for current != nil {
+		if i == index-1 {
+			current.Next = current.Next.Next
+			link.length--
+			return nil
+		}
+		i++
+		current = current.Next
+	}
+
+	return errors.New("delete error")
+}
+
+// Reverse the linked list
+func (link *DoublyLink[T]) Reverse() {
+	current := link.Head
+	var temp *LinkNode[T]
+
+	for current != nil {
+		temp = current.Pre
+		current.Pre = current.Next
+		current.Next = temp
+		current = current.Pre
+	}
+
+	if temp != nil {
+		link.Head = temp.Pre
+	}
+}
+
+// GetMiddleNode return node at middle index of linked list
+func (link *DoublyLink[T]) GetMiddleNode() *LinkNode[T] {
+	if link.Head == nil {
+		return nil
+	}
+	if link.Head.Next == nil {
+		return link.Head
+	}
+	fast := link.Head
+	slow := link.Head
+
+	for fast != nil {
+		fast = fast.Next
+
+		if fast != nil {
+			fast = fast.Next
+			slow = slow.Next
+		} else {
+			return slow
+		}
+	}
+	return slow
+}
+
+// Size return the count of doubly linked list
+func (link *DoublyLink[T]) Size() int {
+	return link.length
+}
+
+// Values return slice of all doubly linklist node value
+func (link *DoublyLink[T]) Values() []T {
+	res := []T{}
+	current := link.Head
+	for current != nil {
+		res = append(res, current.Value)
+		current = current.Next
+	}
+	return res
+}
+
+// Print all nodes info of a linked list
+func (link *DoublyLink[T]) Print() {
+	current := link.Head
+	info := "[ "
+	for current != nil {
+		info += fmt.Sprintf("%+v, ", current)
+		current = current.Next
+	}
+	info += " ]"
+	fmt.Println(info)
+}
diff --git a/datastructure/doublylink_test.go b/datastructure/doublylink_test.go
new file mode 100644
index 0000000..7518966
--- /dev/null
+++ b/datastructure/doublylink_test.go
@@ -0,0 +1,165 @@
+package datastructure
+
+import (
+	"testing"
+
+	"github.com/duke-git/lancet/internal"
+)
+
+func TestDoublyLink_InsertAtFirst(t *testing.T) {
+	assert := internal.NewAssert(t, "TestDoublyLink_InsertAtFirst")
+
+	link := NewDoublyLink[int]()
+	link.InsertAtHead(1)
+	link.InsertAtHead(2)
+	link.InsertAtHead(3)
+	link.Print()
+
+	expected := []int{3, 2, 1}
+	values := link.Values()
+
+	assert.Equal(expected, values)
+}
+
+func TestDoublyLink_InsertAtTail(t *testing.T) {
+	assert := internal.NewAssert(t, "TestDoublyLink_InsertAtTail")
+
+	link := NewDoublyLink[int]()
+	link.InsertAtTail(1)
+	link.InsertAtTail(2)
+	link.InsertAtTail(3)
+	link.Print()
+
+	expected := []int{1, 2, 3}
+	values := link.Values()
+
+	assert.Equal(expected, values)
+}
+
+func TestDoublyLink_InsertAt(t *testing.T) {
+	assert := internal.NewAssert(t, "TestDoublyLink_InsertAt")
+
+	link := NewDoublyLink[int]()
+
+	err := link.InsertAt(1, 1)
+	assert.IsNotNil(err)
+
+	err = link.InsertAt(0, 1)
+	err = link.InsertAt(1, 2)
+	err = link.InsertAt(2, 4)
+	err = link.InsertAt(2, 3)
+
+	if err != nil {
+		t.FailNow()
+	}
+	link.Print()
+
+	expected := []int{1, 2, 3, 4}
+	values := link.Values()
+
+	assert.Equal(expected, values)
+
+}
+
+func TestDoublyLink_DeleteAtHead(t *testing.T) {
+	assert := internal.NewAssert(t, "TestDoublyLink_DeleteAtHead")
+
+	link := NewDoublyLink[int]()
+	err := link.DeleteAtHead()
+	assert.IsNotNil(err)
+
+	link.InsertAtTail(1)
+	link.InsertAtTail(2)
+	link.InsertAtTail(3)
+	link.InsertAtTail(4)
+
+	link.DeleteAtHead()
+	link.Print()
+
+	expected := []int{2, 3, 4}
+	values := link.Values()
+
+	assert.Equal(expected, values)
+}
+
+func TestDoublyLink_DeleteAtTail(t *testing.T) {
+	assert := internal.NewAssert(t, "TestDoublyLink_DeleteAtTail")
+
+	link := NewDoublyLink[int]()
+	err := link.DeleteAtTail()
+	assert.IsNotNil(err)
+
+	link.InsertAtTail(1)
+	link.InsertAtTail(2)
+	link.InsertAtTail(3)
+	link.InsertAtTail(4)
+
+	link.DeleteAtTail()
+	link.Print()
+
+	expected := []int{1, 2, 3}
+	values := link.Values()
+
+	assert.Equal(expected, values)
+}
+
+func TestDoublyLink_DeleteAt(t *testing.T) {
+	assert := internal.NewAssert(t, "TestDoublyLink_DeleteAt")
+
+	link := NewDoublyLink[int]()
+	err := link.DeleteAt(0)
+	assert.IsNotNil(err)
+
+	link.InsertAtTail(1)
+	link.InsertAtTail(2)
+	link.InsertAtTail(3)
+	link.InsertAtTail(4)
+	link.InsertAtTail(5)
+
+	err = link.DeleteAt(5)
+	assert.IsNotNil(err)
+
+	err = link.DeleteAt(0)
+	assert.IsNil(err)
+	assert.Equal([]int{2, 3, 4, 5}, link.Values())
+
+	link.DeleteAt(3)
+	assert.Equal([]int{2, 3, 4}, link.Values())
+
+	link.DeleteAt(1)
+	assert.Equal(2, link.Size())
+	assert.Equal([]int{2, 4}, link.Values())
+}
+
+func TestDoublyLink_Reverse(t *testing.T) {
+	assert := internal.NewAssert(t, "TestDoublyLink_Reverse")
+
+	link := NewDoublyLink[int]()
+	link.InsertAtTail(1)
+	link.InsertAtTail(2)
+	link.InsertAtTail(3)
+	link.InsertAtTail(4)
+
+	link.Reverse()
+	link.Print()
+	assert.Equal([]int{4, 3, 2, 1}, link.Values())
+}
+
+func TestDoublyLink_GetMiddleNode(t *testing.T) {
+	assert := internal.NewAssert(t, "TestDoublyLink_GetMiddleNode")
+
+	link := NewDoublyLink[int]()
+	link.InsertAtTail(1)
+	link.InsertAtTail(2)
+	link.InsertAtTail(3)
+	link.InsertAtTail(4)
+
+	middle1 := link.GetMiddleNode()
+	assert.Equal(3, middle1.Value)
+
+	link.InsertAtTail(5)
+	link.InsertAtTail(6)
+	link.InsertAtTail(7)
+	middle2 := link.GetMiddleNode()
+	assert.Equal(4, middle2.Value)
+}