diff --git a/beacon-chain/blockchain/chain_info.go b/beacon-chain/blockchain/chain_info.go
index 5c53d4582..7fbfb10e3 100644
--- a/beacon-chain/blockchain/chain_info.go
+++ b/beacon-chain/blockchain/chain_info.go
@@ -54,6 +54,7 @@ type HeadFetcher interface {
 	HeadValidatorIndexToPublicKey(ctx context.Context, index types.ValidatorIndex) ([fieldparams.BLSPubkeyLength]byte, error)
 	ProtoArrayStore() *protoarray.Store
 	ChainHeads() ([][32]byte, []types.Slot)
+	IsOptimistic(ctx context.Context) (bool, error)
 	HeadSyncCommitteeFetcher
 	HeadDomainFetcher
 }
@@ -328,6 +329,13 @@ func (s *Service) HeadValidatorIndexToPublicKey(_ context.Context, index types.V
 	return v.PublicKey(), nil
 }
 
+// IsOptimistic returns true if the current head is optimistic.
+func (s *Service) IsOptimistic(ctx context.Context) (bool, error) {
+	s.headLock.RLock()
+	defer s.headLock.RUnlock()
+	return s.cfg.ForkChoiceStore.Optimistic(ctx, s.head.root, s.head.slot)
+}
+
 // SetGenesisTime sets the genesis time of beacon chain.
 func (s *Service) SetGenesisTime(t time.Time) {
 	s.genesisTime = t
diff --git a/beacon-chain/blockchain/chain_info_test.go b/beacon-chain/blockchain/chain_info_test.go
index f31d17825..7fa00e47c 100644
--- a/beacon-chain/blockchain/chain_info_test.go
+++ b/beacon-chain/blockchain/chain_info_test.go
@@ -355,3 +355,14 @@ func TestService_HeadValidatorIndexToPublicKeyNil(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, [fieldparams.BLSPubkeyLength]byte{}, p)
 }
+
+func TestService_IsOptimistic(t *testing.T) {
+	ctx := context.Background()
+	c := &Service{cfg: &config{ForkChoiceStore: protoarray.New(0, 0, [32]byte{})}, head: &head{slot: 101, root: [32]byte{'b'}}}
+	require.NoError(t, c.cfg.ForkChoiceStore.ProcessBlock(ctx, 100, [32]byte{'a'}, [32]byte{}, [32]byte{}, 0, 0))
+	require.NoError(t, c.cfg.ForkChoiceStore.ProcessBlock(ctx, 101, [32]byte{'b'}, [32]byte{'a'}, [32]byte{}, 0, 0))
+
+	opt, err := c.IsOptimistic(ctx)
+	require.NoError(t, err)
+	require.Equal(t, true, opt)
+}
diff --git a/beacon-chain/blockchain/testing/mock.go b/beacon-chain/blockchain/testing/mock.go
index f41a5847b..4a120669e 100644
--- a/beacon-chain/blockchain/testing/mock.go
+++ b/beacon-chain/blockchain/testing/mock.go
@@ -438,3 +438,8 @@ func (s *ChainService) HeadSyncSelectionProofDomain(_ context.Context, _ types.S
 func (s *ChainService) HeadSyncContributionProofDomain(_ context.Context, _ types.Slot) ([]byte, error) {
 	return s.SyncContributionProofDomain, nil
 }
+
+// IsOptimistic mocks the same method in the chain service.
+func (s *ChainService) IsOptimistic(_ context.Context) (bool, error) {
+	return false, nil
+}
diff --git a/beacon-chain/forkchoice/interfaces.go b/beacon-chain/forkchoice/interfaces.go
index cf3ad391e..a1729e743 100644
--- a/beacon-chain/forkchoice/interfaces.go
+++ b/beacon-chain/forkchoice/interfaces.go
@@ -18,9 +18,10 @@ type ForkChoicer interface {
 	ProposerBooster      // ability to boost timely-proposed block roots.
 }
 
-// HeadRetriever retrieves head root of the current chain.
+// HeadRetriever retrieves head root and optimistic info of the current chain.
 type HeadRetriever interface {
 	Head(context.Context, types.Epoch, [32]byte, []uint64, types.Epoch) ([32]byte, error)
+	Optimistic(ctx context.Context, root [32]byte, slot types.Slot) (bool, error)
 }
 
 // BlockProcessor processes the block that's used for accounting fork choice.