A　DC/DC　boost　converter　is　an　essential　subassembly　for　power/energy　transfer　from　a　power　source　to　electrical　facilities.　Polymer　electrolyte　membrane　fuel　cell　(PEMFC)　is　currently　drawing　great　attention　as　the　power　source　for　electric　vehicles.　With　the　coordination　of　a　boost　converter　tackling　with　widely　changing　external　load,　an　electric　vehicle　can　obtain　the　required　voltage　supply　for　its　powertrain　system.　This　paper　focuses　on　PEMFC　power　system　voltage　control　in　face　of　varied　tracking　references　and　disturbance　injections.　An　equivalent　electrical　circuit　model　for　the　PEMFC　and　the　boost　converter　averaging　state　model　are　employed　to　describe　the　entire　power　system.　Then,　a　sliding　mode　control　integrated　with　backstepping　method　is　used　to　provide　the　control　signal　in　the　form　of　the　PWM　duty　ratio,　wherein　the　control　stability　is　ensured　via　suitable　configuration　of　Lyapunov　functions.　Moreover,　an　adaptive　law　for　dealing　with　the　parameter　uncertainties　is　also　adopted.　Finally,　simulation　and　experimental　tests　are　carried　out　to　verify　the　voltage　tracking　effectiveness　of　the　proposed　control　method,　with　external　load　variation　and　parametric　uncertainties　considered　in　the　operation　conditions.　©　2019　IEEE.