diff --git a/beacon-chain/rpc/eth/config/handlers_test.go b/beacon-chain/rpc/eth/config/handlers_test.go
index b269349c3960..813cc7de5aae 100644
--- a/beacon-chain/rpc/eth/config/handlers_test.go
+++ b/beacon-chain/rpc/eth/config/handlers_test.go
@@ -148,6 +148,7 @@ func TestGetSpec(t *testing.T) {
 	config.MaxAttesterSlashingsElectra = 88
 	config.MaxAttestationsElectra = 89
 	config.MaxWithdrawalRequestsPerPayload = 90
+	config.MaxCellsInExtendedMatrix = 91
 
 	var dbp [4]byte
 	copy(dbp[:], []byte{'0', '0', '0', '1'})
@@ -190,7 +191,7 @@ func TestGetSpec(t *testing.T) {
 	data, ok := resp.Data.(map[string]interface{})
 	require.Equal(t, true, ok)
 
-	assert.Equal(t, 152, len(data))
+	assert.Equal(t, 153, len(data))
 	for k, v := range data {
 		t.Run(k, func(t *testing.T) {
 			switch k {
@@ -521,6 +522,8 @@ func TestGetSpec(t *testing.T) {
 				assert.Equal(t, "89", v)
 			case "MAX_WITHDRAWAL_REQUESTS_PER_PAYLOAD":
 				assert.Equal(t, "90", v)
+			case "MAX_CELLS_IN_EXTENDED_MATRIX":
+				assert.Equal(t, "91", v)
 			default:
 				t.Errorf("Incorrect key: %s", k)
 			}
diff --git a/config/params/config.go b/config/params/config.go
index 6b3a07b64ec1..552ac2b9c603 100644
--- a/config/params/config.go
+++ b/config/params/config.go
@@ -270,7 +270,8 @@ type BeaconChainConfig struct {
 	NodeIdBits                      uint64          `yaml:"NODE_ID_BITS" spec:"true"`                       // NodeIdBits defines the bit length of a node id.
 
 	// PeerDAS
-	NumberOfColumns uint64 `yaml:"NUMBER_OF_COLUMNS" spec:"true"` // NumberOfColumns in the extended data matrix.
+	NumberOfColumns          uint64 `yaml:"NUMBER_OF_COLUMNS" spec:"true"`            // NumberOfColumns in the extended data matrix.
+	MaxCellsInExtendedMatrix uint64 `yaml:"MAX_CELLS_IN_EXTENDED_MATRIX" spec:"true"` // MaxCellsInExtendedMatrix is the full data of one-dimensional erasure coding extended blobs (in row major format).
 }
 
 // InitializeForkSchedule initializes the schedules forks baked into the config.
diff --git a/config/params/mainnet_config.go b/config/params/mainnet_config.go
index c7ba47f71812..098ceb5c7dea 100644
--- a/config/params/mainnet_config.go
+++ b/config/params/mainnet_config.go
@@ -310,7 +310,8 @@ var mainnetBeaconConfig = &BeaconChainConfig{
 	NodeIdBits:                      256,
 
 	// PeerDAS
-	NumberOfColumns: 128,
+	NumberOfColumns:          128,
+	MaxCellsInExtendedMatrix: 768,
 }
 
 // MainnetTestConfig provides a version of the mainnet config that has a different name