The role of aquatic arthropod diversity and community interactions of larval mosquitoes are important for understanding mosquito population dynamics. We tested the effects of aquatic macrophyte diversity and habitat structural complexity in shaping the predator and competitor invertebrate communities associated with mosquito larvae. Experimental mesocosms were planted with live aquatic macrophytes and allowed to be naturally colonized by local invertebrates. Results indicated a positive effect of macrophyte diversity on competitor diversity and a negative effect on predator diversity. In turn, predator diversity negatively impacted mosquito abundance through a direct effect, while competitor diversity showed an indirect negative effect on mosquito larval abundance through its positive effect on predator diversity. The enhancement of aquatic macrophyte diversity and structural complexity has practical applications for the reduction of mosquito populations in managed systems where complete source elimination is not possible.