diff --git a/CHANGELOG.md b/CHANGELOG.md
index d99901f0e169..83aba3f35139 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -40,6 +40,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 ### Bug Fixes
 
 * (cli) [#17188](https://github.com/cosmos/cosmos-sdk/pull/17188) Fix `--output-document` flag in `tx multi-sign`.
+* (x/auth) [#17209](https://github.com/cosmos/cosmos-sdk/pull/17209) Internal error on AccountInfo when account's public key is not set.
 
 ## [v0.47.4](https://github.com/cosmos/cosmos-sdk/releases/tag/v0.47.4) - 2023-07-17
 
diff --git a/x/auth/keeper/grpc_query.go b/x/auth/keeper/grpc_query.go
index 983da9c5a3a8..7acb77134c68 100644
--- a/x/auth/keeper/grpc_query.go
+++ b/x/auth/keeper/grpc_query.go
@@ -231,9 +231,14 @@ func (ak AccountKeeper) AccountInfo(goCtx context.Context, req *types.QueryAccou
 		return nil, status.Errorf(codes.NotFound, "account %s not found", req.Address)
 	}
 
-	pkAny, err := codectypes.NewAnyWithValue(account.GetPubKey())
-	if err != nil {
-		return nil, status.Errorf(codes.Internal, err.Error())
+	// if there is no public key, avoid serializing the nil value
+	pubKey := account.GetPubKey()
+	var pkAny *codectypes.Any
+	if pubKey != nil {
+		pkAny, err = codectypes.NewAnyWithValue(account.GetPubKey())
+		if err != nil {
+			return nil, status.Errorf(codes.Internal, err.Error())
+		}
 	}
 
 	return &types.QueryAccountInfoResponse{
diff --git a/x/auth/keeper/grpc_query_test.go b/x/auth/keeper/grpc_query_test.go
index 5a9ebbd2ea22..55b08ad20ad1 100644
--- a/x/auth/keeper/grpc_query_test.go
+++ b/x/auth/keeper/grpc_query_test.go
@@ -532,3 +532,17 @@ func (suite *KeeperTestSuite) TestQueryAccountInfo() {
 	suite.Require().NoError(err)
 	suite.Require().Equal(pkBz, res.Info.PubKey.Value)
 }
+
+func (suite *KeeperTestSuite) TestQueryAccountInfoWithoutPubKey() {
+	acc := suite.accountKeeper.NewAccountWithAddress(suite.ctx, addr)
+	suite.accountKeeper.SetAccount(suite.ctx, acc)
+
+	res, err := suite.queryClient.AccountInfo(context.Background(), &types.QueryAccountInfoRequest{
+		Address: addr.String(),
+	})
+
+	suite.Require().NoError(err)
+	suite.Require().NotNil(res.Info)
+	suite.Require().Equal(addr.String(), res.Info.Address)
+	suite.Require().Nil(res.Info.PubKey)
+}