diff --git a/pkg/bbgo/activeorderbook.go b/pkg/bbgo/activeorderbook.go
index 104c9f349..567014665 100644
--- a/pkg/bbgo/activeorderbook.go
+++ b/pkg/bbgo/activeorderbook.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/json"
 	"sort"
+	"sync"
 	"time"
 
 	"github.com/pkg/errors"
@@ -32,6 +33,8 @@ type ActiveOrderBook struct {
 	// sig is the order update signal
 	// this signal will be emitted when a new order is added or removed.
 	C sigchan.Chan
+
+	mu sync.Mutex
 }
 
 func NewActiveOrderBook(symbol string) *ActiveOrderBook {
@@ -57,7 +60,7 @@ func (b *ActiveOrderBook) BindStream(stream types.Stream) {
 }
 
 func (b *ActiveOrderBook) waitClear(ctx context.Context, order types.Order, waitTime, timeout time.Duration) (bool, error) {
-	if !b.Exists(order) {
+	if !b.orders.Exists(order.OrderID) {
 		return true, nil
 	}
 
@@ -68,7 +71,7 @@ func (b *ActiveOrderBook) waitClear(ctx context.Context, order types.Order, wait
 		case <-b.C:
 		}
 
-		clear := !b.Exists(order)
+		clear := !b.orders.Exists(order.OrderID)
 
 		select {
 		case <-timeoutC:
@@ -146,7 +149,7 @@ func (b *ActiveOrderBook) FastCancel(ctx context.Context, ex types.Exchange, ord
 	}
 
 	for _, o := range orders {
-		b.Remove(o)
+		b.orders.Remove(o.OrderID)
 	}
 	return nil
 }
@@ -269,45 +272,53 @@ func (b *ActiveOrderBook) update(orders ...types.Order) {
 // When the order is cancelled, it will be removed from the internal order storage.
 func (b *ActiveOrderBook) Update(order types.Order) {
 	hasSymbol := len(b.Symbol) > 0
-
 	if hasSymbol && order.Symbol != b.Symbol {
 		return
 	}
 
+	b.mu.Lock()
 	if !b.orders.Exists(order.OrderID) {
 		b.pendingOrderUpdates.Add(order)
+		b.mu.Unlock()
 		return
 	}
 
 	switch order.Status {
 	case types.OrderStatusFilled:
 		// make sure we have the order and we remove it
-		if b.Remove(order) {
+		removed := b.orders.Remove(order.OrderID)
+		b.mu.Unlock()
+
+		if removed {
 			b.EmitFilled(order)
 		}
 		b.C.Emit()
 
 	case types.OrderStatusPartiallyFilled:
 		b.update(order)
+		b.mu.Unlock()
 
 	case types.OrderStatusNew:
 		b.update(order)
+		b.mu.Unlock()
+
 		b.C.Emit()
 
 	case types.OrderStatusCanceled, types.OrderStatusRejected:
 		// TODO: note that orders transit to "canceled" may have partially filled
+		log.Debugf("[ActiveOrderBook] order is %s, removing order %s", order.Status, order)
+		b.orders.Remove(order.OrderID)
+		b.mu.Unlock()
+
 		if order.Status == types.OrderStatusCanceled {
 			b.EmitCanceled(order)
 		}
-
-		log.Debugf("[ActiveOrderBook] order is %s, removing order %s", order.Status, order)
-		b.Remove(order)
 		b.C.Emit()
 
 	default:
+		b.mu.Unlock()
 		log.Warnf("[ActiveOrderBook] unhandled order status: %s", order.Status)
 	}
-
 }
 
 func (b *ActiveOrderBook) Add(orders ...types.Order) {
@@ -339,7 +350,7 @@ func (b *ActiveOrderBook) add(order types.Order) {
 		// so, when it's not status=new, we should trigger order update handler
 		if order.Status != types.OrderStatusNew {
 			// emit the order update handle function to trigger callback
-			b.orderUpdateHandler(order)
+			b.Update(order)
 		}
 
 	} else {
@@ -348,6 +359,8 @@ func (b *ActiveOrderBook) add(order types.Order) {
 }
 
 func (b *ActiveOrderBook) Exists(order types.Order) bool {
+	b.mu.Lock()
+	defer b.mu.Unlock()
 	return b.orders.Exists(order.OrderID)
 }
 
@@ -356,6 +369,8 @@ func (b *ActiveOrderBook) Get(orderID uint64) (types.Order, bool) {
 }
 
 func (b *ActiveOrderBook) Remove(order types.Order) bool {
+	b.mu.Lock()
+	defer b.mu.Unlock()
 	return b.orders.Remove(order.OrderID)
 }
 
diff --git a/pkg/bbgo/activeorderbook_test.go b/pkg/bbgo/activeorderbook_test.go
index fdd4ea9e9..848e07bc9 100644
--- a/pkg/bbgo/activeorderbook_test.go
+++ b/pkg/bbgo/activeorderbook_test.go
@@ -22,7 +22,7 @@ func TestActiveOrderBook_pendingOrders(t *testing.T) {
 
 	// if we received filled order first
 	// should be added to pending orders
-	ob.orderUpdateHandler(types.Order{
+	ob.Update(types.Order{
 		OrderID: 99,
 		SubmitOrder: types.SubmitOrder{
 			Symbol:       "BTCUSDT",
@@ -63,5 +63,4 @@ func TestActiveOrderBook_pendingOrders(t *testing.T) {
 	})
 
 	assert.True(t, filled, "filled event should be fired")
-
 }