diff --git a/cmd/mist/assets/qml/views/miner.qml b/cmd/mist/assets/qml/views/miner.qml
index e0182649f..193ce37be 100644
--- a/cmd/mist/assets/qml/views/miner.qml
+++ b/cmd/mist/assets/qml/views/miner.qml
@@ -46,6 +46,7 @@ Rectangle {
 						text: "Start"
 						onClicked: {
 							eth.setGasPrice(minGasPrice.text || "10000000000000");
+							eth.setExtra(blockExtra.text)
 							if (eth.toggleMining()) {
 								this.text = "Stop";
 							} else {
@@ -55,6 +56,7 @@ Rectangle {
 					}
 
 					Rectangle {
+						id: minGasPriceRect
 						anchors.top: parent.top
 						anchors.topMargin: 2
 						width: 200
@@ -65,6 +67,23 @@ Rectangle {
 							validator: RegExpValidator { regExp: /\d*/ }
 						}
 					}
+
+					Rectangle {
+						width: 300
+						anchors {
+							left: minGasPriceRect.right
+							leftMargin: 5
+							top: parent.top
+							topMargin: 2
+						}
+
+						TextField {
+							id: blockExtra
+							placeholderText: "Extra"
+							width: parent.width
+							maximumLength: 1024
+						}
+					}
 				}
 			}
 
diff --git a/cmd/mist/ui_lib.go b/cmd/mist/ui_lib.go
index 0aabb87d0..933c323de 100644
--- a/cmd/mist/ui_lib.go
+++ b/cmd/mist/ui_lib.go
@@ -279,6 +279,10 @@ func (self *UiLib) SetGasPrice(price string) {
 	self.miner.MinAcceptedGasPrice = ethutil.Big(price)
 }
 
+func (self *UiLib) SetExtra(extra string) {
+	self.miner.Extra = extra
+}
+
 func (self *UiLib) ToggleMining() bool {
 	if !self.miner.Mining() {
 		self.miner.Start()
diff --git a/miner/miner.go b/miner/miner.go
index 949227d98..f80ae51c6 100644
--- a/miner/miner.go
+++ b/miner/miner.go
@@ -69,6 +69,7 @@ type Miner struct {
 	mining bool
 
 	MinAcceptedGasPrice *big.Int
+	Extra               string
 }
 
 func New(coinbase []byte, eth *eth.Ethereum) *Miner {
@@ -178,6 +179,7 @@ func (self *Miner) mine() {
 		chainMan       = self.eth.ChainManager()
 		block          = chainMan.NewBlock(self.Coinbase)
 	)
+	block.Header().Extra = self.Extra
 
 	// Apply uncles
 	if len(self.uncles) > 0 {