diff --git a/docs/eventing-api.md b/docs/eventing-api.md
index 2244e88604f..cefd2e02164 100644
--- a/docs/eventing-api.md
+++ b/docs/eventing-api.md
@@ -504,6 +504,23 @@ For more details: <a href="https://github.com/knative/eventing/issues/5811">http
 - <a href="https://en.wikipedia.org/wiki/ISO_8601">https://en.wikipedia.org/wiki/ISO_8601</a></p>
 </td>
 </tr>
+<tr>
+<td>
+<code>format</code><br/>
+<em>
+string
+</em>
+</td>
+<td>
+<em>(Optional)</em>
+<p>format specifies the desired event format for the cloud event.
+It can be one of the following values:
+- nil: default value, no specific format required.
+- &ldquo;JSON&rdquo;: indicates the event should be in structured mode.
+- &ldquo;binary&rdquo;: indicates the event should be in binary mode.
+- &ldquo;ingress&rdquo;: indicates the event should be in ingress mode.</p>
+</td>
+</tr>
 </tbody>
 </table>
 <h3 id="duck.knative.dev/v1.DeliveryStatus">DeliveryStatus
diff --git a/pkg/apis/duck/v1/delivery_types.go b/pkg/apis/duck/v1/delivery_types.go
index 48048a09d6e..b70b33d65da 100644
--- a/pkg/apis/duck/v1/delivery_types.go
+++ b/pkg/apis/duck/v1/delivery_types.go
@@ -18,6 +18,7 @@ package v1
 
 import (
 	"context"
+	"strings"
 
 	"github.com/rickb777/date/period"
 	"knative.dev/pkg/apis"
@@ -81,6 +82,15 @@ type DeliverySpec struct {
 	//
 	// +optional
 	RetryAfterMax *string `json:"retryAfterMax,omitempty"`
+
+	// format specifies the desired event format for the cloud event.
+	// It can be one of the following values:
+	// - nil: default value, no specific format required.
+	// - "JSON": indicates the event should be in structured mode.
+	// - "binary": indicates the event should be in binary mode.
+	// - "ingress": indicates the event should be in ingress mode.
+	//+optional
+	Format *string `json:"format,omitempty"`
 }
 
 func (ds *DeliverySpec) Validate(ctx context.Context) *apis.FieldError {
@@ -123,6 +133,17 @@ func (ds *DeliverySpec) Validate(ctx context.Context) *apis.FieldError {
 		}
 	}
 
+	if ds.Format != nil {
+		validFormats := map[string]bool{
+			"json":    true,
+			"binary":  true,
+			"ingress": true,
+		}
+		if _, ok := validFormats[strings.ToLower(*ds.Format)]; !ok {
+			errs = errs.Also(apis.ErrInvalidValue(*ds.Format, "format"))
+		}
+	}
+
 	if ds.RetryAfterMax != nil {
 		if feature.FromContext(ctx).IsEnabled(feature.DeliveryRetryAfter) {
 			p, me := period.Parse(*ds.RetryAfterMax)
diff --git a/pkg/apis/duck/v1/delivery_types_test.go b/pkg/apis/duck/v1/delivery_types_test.go
index 5ac8f469d56..9605e21f588 100644
--- a/pkg/apis/duck/v1/delivery_types_test.go
+++ b/pkg/apis/duck/v1/delivery_types_test.go
@@ -141,7 +141,27 @@ func TestDeliverySpecValidation(t *testing.T) {
 		want: func() *apis.FieldError {
 			return apis.ErrDisallowedFields("retryAfterMax")
 		}(),
-	}}
+	},
+		{
+			name: "valid format JSON",
+			spec: &DeliverySpec{Format: pointer.String("json")},
+			want: nil,
+		},
+		{
+			name: "vaalid format binary",
+			spec: &DeliverySpec{Format: pointer.String("binary")},
+			want: nil,
+		}, {
+			name: "valid format ingress",
+			spec: &DeliverySpec{Format: pointer.String("ingress")},
+			want: nil,
+		}, {
+			name: "invalid format",
+			spec: &DeliverySpec{Format: pointer.String("invalid")},
+			want: func() *apis.FieldError {
+				return apis.ErrInvalidValue("invalid", "format")
+			}(),
+		}}
 
 	for _, test := range tests {
 		t.Run(test.name, func(t *testing.T) {
diff --git a/pkg/apis/duck/v1/zz_generated.deepcopy.go b/pkg/apis/duck/v1/zz_generated.deepcopy.go
index d7965aaf4c6..313f09afa74 100644
--- a/pkg/apis/duck/v1/zz_generated.deepcopy.go
+++ b/pkg/apis/duck/v1/zz_generated.deepcopy.go
@@ -201,6 +201,11 @@ func (in *DeliverySpec) DeepCopyInto(out *DeliverySpec) {
 		*out = new(string)
 		**out = **in
 	}
+	if in.Format != nil {
+		in, out := &in.Format, &out.Format
+		*out = new(string)
+		**out = **in
+	}
 	return
 }