Water electrolysis is an available way to obtain green hydrogen. The development of highly efficient electrocatalysts is a current research hotspot for water splitting, but it remains challenging. Herein, we demonstrate the synthesis of a robust bifunctional multi-metal electrocatalysts toward water splitting via the rapid Joule-heating conversion of metal precursors. The composition and morphology were well regulated via altering the ratio of metal precursors. In particular, the trimetal MoC/FeO/CoO/carbon cloth (CC) electrode revealed the outstanding bifunctional electrocatalytic performance due to the unique composition and large electrochemical active surface area. Typically, the MoC/FeO/CoO/CC catalyst needed low overpotentials of 121 and 268 mV to reach 10 mA·cm^-2 toward HER and OER in 1 mol·L^-1 KOH solution, respectively. When used as both cathode and anode, a small potential of 1.69 V was required to achieve 10 mA·cm^-2 for overall water splitting and an impressive stability for 25 h was observed. This facile and rapid Joule heating strategy offers guideline for rational manufacture of bimetal or multi-metal electrocatalysts toward diverse application.