In this paper, we study the ground state of the rotating spin-1 spin–orbit coupling (SOC) Bose–Einstein condensates (BECs) in a hamornic trap. Within the framework of mean-field theory, the effects of unequal atomic mass, spin–orbit coupling and rotation frequency are investigated. Our results display that the combined effects of these parameters create rich vortex structure. We also discuss the dependence of angular momentum per atom and spin polarisation as a function of spin–orbit coupling strength, showing that angular momentum increases with increasing spin–orbit coupling strength for a fixed rotation frequency and in this process first-order phase transition does not occur.