diff --git a/pkg/bbgo/session.go b/pkg/bbgo/session.go
index 8a9bef426..c6647bc4f 100644
--- a/pkg/bbgo/session.go
+++ b/pkg/bbgo/session.go
@@ -886,15 +886,16 @@ func (session *ExchangeSession) InitExchange(name string, ex types.Exchange) err
 	return nil
 }
 
-func (session *ExchangeSession) MarginType() string {
-	margin := "none"
+func (session *ExchangeSession) MarginType() types.MarginType {
 	if session.Margin {
-		margin = "margin"
 		if session.IsolatedMargin {
-			margin = "isolated"
+			return types.MarginTypeIsolatedMargin
+		} else {
+			return types.MarginTypeCrossMargin
 		}
 	}
-	return margin
+
+	return types.MarginTypeSpot
 }
 
 func (session *ExchangeSession) metricsBalancesUpdater(balances types.BalanceMap) {
diff --git a/pkg/types/futures.go b/pkg/types/futures.go
new file mode 100644
index 000000000..ef19e0a2d
--- /dev/null
+++ b/pkg/types/futures.go
@@ -0,0 +1,42 @@
+package types
+
+import "github.com/c9s/bbgo/pkg/fixedpoint"
+
+type FuturesExchange interface {
+	UseFutures()
+	UseIsolatedFutures(symbol string)
+	GetFuturesSettings() FuturesSettings
+}
+
+type FuturesSettings struct {
+	IsFutures             bool
+	IsIsolatedFutures     bool
+	IsolatedFuturesSymbol string
+}
+
+func (s FuturesSettings) GetFuturesSettings() FuturesSettings {
+	return s
+}
+
+func (s *FuturesSettings) UseFutures() {
+	s.IsFutures = true
+}
+
+func (s *FuturesSettings) UseIsolatedFutures(symbol string) {
+	s.IsFutures = true
+	s.IsIsolatedFutures = true
+	s.IsolatedFuturesSymbol = symbol
+}
+
+// FuturesUserAsset define cross/isolated futures account asset
+type FuturesUserAsset struct {
+	Asset                  string           `json:"asset"`
+	InitialMargin          fixedpoint.Value `json:"initialMargin"`
+	MaintMargin            fixedpoint.Value `json:"maintMargin"`
+	MarginBalance          fixedpoint.Value `json:"marginBalance"`
+	MaxWithdrawAmount      fixedpoint.Value `json:"maxWithdrawAmount"`
+	OpenOrderInitialMargin fixedpoint.Value `json:"openOrderInitialMargin"`
+	PositionInitialMargin  fixedpoint.Value `json:"positionInitialMargin"`
+	UnrealizedProfit       fixedpoint.Value `json:"unrealizedProfit"`
+	WalletBalance          fixedpoint.Value `json:"walletBalance"`
+}
diff --git a/pkg/types/margin.go b/pkg/types/margin.go
index a546f2d69..97875fccf 100644
--- a/pkg/types/margin.go
+++ b/pkg/types/margin.go
@@ -7,44 +7,13 @@ import (
 	"github.com/c9s/bbgo/pkg/fixedpoint"
 )
 
-type FuturesExchange interface {
-	UseFutures()
-	UseIsolatedFutures(symbol string)
-	GetFuturesSettings() FuturesSettings
-}
+type MarginType string
 
-type FuturesSettings struct {
-	IsFutures             bool
-	IsIsolatedFutures     bool
-	IsolatedFuturesSymbol string
-}
-
-func (s FuturesSettings) GetFuturesSettings() FuturesSettings {
-	return s
-}
-
-func (s *FuturesSettings) UseFutures() {
-	s.IsFutures = true
-}
-
-func (s *FuturesSettings) UseIsolatedFutures(symbol string) {
-	s.IsFutures = true
-	s.IsIsolatedFutures = true
-	s.IsolatedFuturesSymbol = symbol
-}
-
-// FuturesUserAsset define cross/isolated futures account asset
-type FuturesUserAsset struct {
-	Asset                  string           `json:"asset"`
-	InitialMargin          fixedpoint.Value `json:"initialMargin"`
-	MaintMargin            fixedpoint.Value `json:"maintMargin"`
-	MarginBalance          fixedpoint.Value `json:"marginBalance"`
-	MaxWithdrawAmount      fixedpoint.Value `json:"maxWithdrawAmount"`
-	OpenOrderInitialMargin fixedpoint.Value `json:"openOrderInitialMargin"`
-	PositionInitialMargin  fixedpoint.Value `json:"positionInitialMargin"`
-	UnrealizedProfit       fixedpoint.Value `json:"unrealizedProfit"`
-	WalletBalance          fixedpoint.Value `json:"walletBalance"`
-}
+const (
+	MarginTypeSpot           MarginType = "spot"
+	MarginTypeCrossMargin    MarginType = "cross_margin"
+	MarginTypeIsolatedMargin MarginType = "isolated_margin"
+)
 
 type MarginExchange interface {
 	UseMargin()