diff --git a/pkg/stacker/convert.go b/pkg/stacker/convert.go
index ebacaf5f..f270e82d 100644
--- a/pkg/stacker/convert.go
+++ b/pkg/stacker/convert.go
@@ -176,6 +176,14 @@ func (c *Converter) convertCommand(cmd *Command) error {
 			c.env = map[string]string{}
 		}
 
+		// Dockerfile ENV defines build and runtime variables.
+		// For equivalent in stacker, also add them to layer's
+		// Environment(runtime).
+		//
+		if layer.Environment == nil {
+			layer.Environment = map[string]string{}
+		}
+
 		// parser returns key, value, sep for ENV since v0.16.1
 		// https://github.com/moby/buildkit/commit/6cfa4599029db7f2e6e83feaaa33984785ddd147
 		if len(cmd.Value) < 3 {
@@ -207,11 +215,8 @@ func (c *Converter) convertCommand(cmd *Command) error {
 				}
 			}
 
-			if c.env == nil {
-				c.env = map[string]string{}
-			}
-
 			c.env[key] = val
+			layer.Environment[key] = val
 		}
 	case "workdir":
 		layer.Run = append(layer.Run, fmt.Sprintf("mkdir -p %s", cmd.Value[0]))
diff --git a/pkg/stacker/convert_test.go b/pkg/stacker/convert_test.go
index 720beacd..827e05dd 100644
--- a/pkg/stacker/convert_test.go
+++ b/pkg/stacker/convert_test.go
@@ -22,8 +22,13 @@ func TestConverterConvertCommandErrors(t *testing.T) {
 		},
 		{
 			name: "invalid env",
-			c:    NewConverter(&ConvertArgs{}),
-			cmd:  &Command{Cmd: "env", Original: "ENV FOO", Value: []string{"FOO"}},
+			c: func() *Converter {
+				c := NewConverter(&ConvertArgs{})
+				c.currLayer = "layer"
+				c.output[c.currLayer] = &types.Layer{}
+				return c
+			}(),
+			cmd: &Command{Cmd: "env", Original: "ENV FOO", Value: []string{"FOO"}},
 		},
 		{
 			name: "invalid arg",