It　is　crucial　to　accurately　calculate　the　cost　function　of　the　energy　management　strategy　(EMS)　of　the　hybrid　powertrain　to　improve　the　hydrogen　economy　of　the　system.　This　paper　proposes　an　EMS　for　fuel　cell　hybrid　electric　vehicles　(FCHEV)　based　on　improved　dynamic　programming　(DP)　and　air　supply　optimization　to　improve　economy　and　reliability.　Taking　the　maximum　net　power　output　of　the　FC　system　as　the　target,　the　optimal　oxygen　excess　ratio　(OER)　and　cathode　pressure　of　the　FC　system　under　different　current　densities　are　solved　by　using　PSO.　A　velocity　prediction　method　based　on　Bi-LSTM　is　developed　to　predict　short-term　velocity　changes　in　real　time.　The　DP　algorithm　is　introduced　and　the　EMS　of　the　DP　algorithm　based　on　short-term　velocity　prediction　is　developed　for　real-time　hybrid　powertrain　optimization　and　management.　Based　on　the　results　of　energy　allocation　and　optimal　gas　supply　conditions　of　FCs,　the　cost　function　of　EMS　is　modified　to　reallocate　the　power　of　the　FC　system　and　battery.　The　results　demonstrate　that　the　proposed　method　achieves　the　lowest　hydrogen　consumption　compared　to　the　other　two　algorithms.　Remarkably,　it　reduces　the　fuel　cost　by　up　to　8.85　%　compared　to　the　commonly　used　online　DP　algorithm.