Understanding the shape effect of hydroxyapatite (HAp) microparticles on cellular behavior is important for enabling new kinds of biological and biomedical applications. However, it is still a challenge to prepare HAp microparticles with different shapes but similar physicochemical properties, and then to investigate their relationships with cellular behavior. Herein, we developed a novel, facile route to regulate the morphology of HAp microparticles, and investigated the interaction between the particles and bone marrow mesenchymal stem cells (BMSCs). Our results revealed that the shape of HAp has a strong influence on cellular behavior, and that the sphere-like particles performed better than the rod-like particles. These findings highlight the importance of the shape characteristics of HAp microparticles, and may provide new insights for the utility of HAp-based materials.