This　paper　presents　an　online　feedback　hybrid　control　strategy　consisting　of　optimal　switching　positions　and　optimal　tractive　efforts　for　urban　train　energy-saving　optimal　operation.　Firstly,　we　use　a　train　dynamic　model　by　taking　train　position　as　independent　variable,　speed　and　time　as　state　variables.　Secondly,　we　establish　the　train　energy　saving　operation　optimization　problem　by　applying　the　result　obtained　by　Pentriagin’s　Maximum　Principle　(PMP)　that　the　optimal　tractive　efforts　consist　of　a　fixed　sequence　of　modes　of　tractive　efforts.　Thirdly,　we　present　an　online　hybrid　control　strategy　by　online　optimizing　the　switching　positions　of　these　modes　and　meanwhile　invoking　these　traction　forces.　Here,　the　optimal　tractive　efforts　are　in　feedback　form　of　the　train　speed　and　thus　this　online　hybrid　control　strategy　is　in　form　of　feedback.　The　discrete　dynamic　programming　algorithm　is　used　to　online　search　for　the　remaining　switching　positions　of　the　train　optimal　modes.　Finally,　this　method　is　compared　with　the　traditional　discrete　dynamic　programming　method　for　obtaining　the　optimal　train　speed　curve　optimization.　The　effectiveness　of　the　proposed　method　and　the　advantages　of　computational　efficiency　and　capacity　of　resisting　disturbance　are　verified　by　a　simulation　example.　©　2022,　The　Author(s),　under　exclusive　license　to　Springer　Nature　Singapore　Pte　Ltd.