diff --git a/CHANGELOG.md b/CHANGELOG.md
index b05f1e9e..6edb5845 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,7 @@
 ## HEAD
 
 - iovnscli: fix has-superuser bool flag bug
+- iovnsd: fix duplicate blockchain targets ID
 - remove flush domain feature
 
 ## v0.2.4
diff --git a/x/domain/handler.go b/x/domain/handler.go
index 2c3a5bfa..61923681 100644
--- a/x/domain/handler.go
+++ b/x/domain/handler.go
@@ -233,8 +233,15 @@ func handleMsgRegisterAccount(ctx sdk.Context, k keeper.Keeper, msg *types.MsgRe
 func validateBlockchainTargets(targets []types.BlockchainAddress, conf configuration.Config) error {
 	validBlockchainID := regexp.MustCompile(conf.ValidBlockchainID)
 	validBlockchainAddress := regexp.MustCompile(conf.ValidBlockchainAddress)
+	// create blockchain targets set to identify duplicates
+	sets := make(map[string]struct{}, len(targets))
 	// iterate over targets to check their validity
 	for _, target := range targets {
+		// check if blockchain ID was already specified
+		if _, ok := sets[target.ID]; ok {
+			return fmt.Errorf("duplicate blockchain ID: %s", target)
+		}
+		sets[target.ID] = struct{}{}
 		// is blockchain id valid?
 		if !validBlockchainID.MatchString(target.ID) {
 			return fmt.Errorf("%s is not a valid blockchain ID", target.ID)
diff --git a/x/domain/handler_test.go b/x/domain/handler_test.go
index e653984f..f0088907 100644
--- a/x/domain/handler_test.go
+++ b/x/domain/handler_test.go
@@ -2107,3 +2107,43 @@ func Test_handlerMsgTransferDomain(t *testing.T) {
 
 	runTests(t, cases)
 }
+
+func Test_validateBlockchainTargets(t *testing.T) {
+	type args struct {
+		targets []types.BlockchainAddress
+		conf    configuration.Config
+	}
+	tests := []struct {
+		name    string
+		args    args
+		wantErr bool
+	}{
+		{
+			name: "duplicate blockchain target",
+			args: args{
+				targets: []types.BlockchainAddress{
+					{
+						ID:      "duplicate",
+						Address: "does not matter",
+					},
+					{
+						ID:      "duplicate",
+						Address: "does not matter",
+					},
+				},
+				conf: configuration.Config{
+					ValidBlockchainID:      regexMatchAll,
+					ValidBlockchainAddress: regexMatchAll,
+				},
+			},
+			wantErr: true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if err := validateBlockchainTargets(tt.args.targets, tt.args.conf); (err != nil) != tt.wantErr {
+				t.Errorf("validateBlockchainTargets() error = %v, wantErr %v", err, tt.wantErr)
+			}
+		})
+	}
+}