The nonsimilar boundary-layer solutions are presented to study the mixed convective micropolar fluid flow about a rotating cone. The transformed boundary-layer equations contain an important mixed convection parameter that determines the relative importance of the free convection on forced (rotational) convection. Numerical solutions are presented for a range of values of the material parameters, the buoyancy parameter, and Prandtl number of the fluid. A discussion is provided for the microrotation boundary conditions and their influence on the velocity, gyration, and heat transfer fields.