diff --git a/apis/opts/config/ulimit_test.go b/apis/opts/config/ulimit_test.go
new file mode 100644
index 000000000..0187c72be
--- /dev/null
+++ b/apis/opts/config/ulimit_test.go
@@ -0,0 +1,177 @@
+package config
+
+import (
+	"fmt"
+	"reflect"
+	"testing"
+
+	"github.com/alibaba/pouch/apis/types"
+	units "github.com/docker/go-units"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestUlimitSet(t *testing.T) {
+	type args struct {
+		val string
+	}
+	tests := []struct {
+		name    string
+		args    args
+		err     error
+		wantErr bool
+		wantStr string
+	}{
+		{
+			name: "valid ulimit format 1",
+			args: args{
+				val: "nofile=512:1024",
+			},
+			wantErr: false,
+		},
+		{
+			name: "valid ulimit format 2",
+			args: args{
+				val: "nofile=1024",
+			},
+			wantErr: false,
+		},
+		{
+			name: "valid ulimit format 3",
+			args: args{
+				val: "cpu=2:4",
+			},
+			wantErr: false,
+		},
+		{
+			name: "valid ulimit format 4",
+			args: args{
+				val: "cpu=6",
+			},
+			wantErr: false,
+		},
+		{
+			name: "invalid ulimit value type 1",
+			args: args{
+				val: "",
+			},
+			wantErr: true,
+			err:     fmt.Errorf("invalid ulimit argument: "),
+		},
+		{
+			name: "invalid ulimit value type 2",
+			args: args{
+				val: "nofile=512:1024:2048",
+			},
+			wantErr: true,
+			err:     fmt.Errorf("too many limit value arguments - 512:1024:2048, can only have up to two, `soft[:hard]`"),
+		},
+		{
+			name: "the hard ulimit value is less than soft",
+			args: args{
+				val: "nofile=1024:1",
+			},
+			wantErr: true,
+			err:     fmt.Errorf("ulimit soft limit must be less than or equal to hard limit: 1024 > 1"),
+		},
+		{
+			name: "bad ulimit format",
+			args: args{
+				val: "cpu:512:1024",
+			},
+			wantErr: true,
+			err:     fmt.Errorf("invalid ulimit argument: cpu:512:1024"),
+		},
+		{
+			name: "invalid ulimit type",
+			args: args{
+				val: "foo=1024:1024",
+			},
+			wantErr: true,
+			err:     fmt.Errorf("invalid ulimit type: foo"),
+		},
+	}
+	{
+		ul := &Ulimit{}
+		for _, tt := range tests {
+			t.Run(tt.name, func(t *testing.T) {
+				err := ul.Set(tt.args.val)
+				if (err != nil) != tt.wantErr {
+					t.Errorf("Ulimit.Set() error = %v, wantErr %v", err, tt.wantErr)
+				}
+				if (tt.err != nil) && !reflect.DeepEqual(err, tt.err) {
+					t.Errorf("Ulimit.Set() = %v, want %v", err, tt.err)
+				}
+			})
+		}
+	}
+}
+
+func TestUlimitType(t *testing.T) {
+	type args struct {
+		val string
+	}
+	tests := []struct {
+		name    string
+		args    args
+		err     error
+		wantErr bool
+		wantStr string
+	}{
+		{
+			name:    "get type of Ulimit",
+			wantErr: false,
+			wantStr: "ulimit",
+		},
+	}
+	{
+		ul := &Ulimit{}
+		for _, tt := range tests {
+			t.Run(tt.name, func(t *testing.T) {
+				out := ul.Type()
+				if !tt.wantErr && !reflect.DeepEqual(out, tt.wantStr) {
+					t.Errorf("Ulimit.String() = %v, want %v", out, tt.wantStr)
+				}
+			})
+		}
+	}
+}
+
+func TestUlimitValue(t *testing.T) {
+	assert := assert.New(t)
+	type args struct {
+		values map[string]*units.Ulimit
+	}
+	tests := []struct {
+		name string
+		args args
+		want types.Ulimit
+	}{
+		{
+			name: "get all values as type Ulimit",
+			want: types.Ulimit{
+				Name: "nofile",
+				Hard: int64(1024),
+				Soft: int64(512),
+			},
+			args: args{
+				values: map[string]*units.Ulimit{
+					"a": {Name: "nofile", Hard: int64(1024), Soft: int64(512)},
+				},
+			},
+		},
+	}
+	{
+		for _, tt := range tests {
+			t.Run(tt.name, func(t *testing.T) {
+				ul := Ulimit{values: tt.args.values}
+				got := ul.Value()
+				assert.NotEmpty(t, got)
+				for _, v := range got {
+					if !reflect.DeepEqual(*v, tt.want) {
+						t.Errorf("ul.value() = %v, want %v", *v, tt.want)
+					}
+				}
+			})
+		}
+	}
+}