This paper is concerned with the large time decay rates of the two-dimensional (2D) micropolar equations with zero angular viscosity. Based on the generalized Fourier splitting methods and low frequency effect analysis, we firstly obtain the solutions decay as ‖ u ‖ L 2 + ‖ ω ‖ L 2 ≤ C (1 + t) - 1 2 . Moreover, by exploring the new structure of the system, we obtain a new improved decay rates ‖ ω ‖ L 2 + ‖ ∇ u ‖ L 2 ≤ C (1 + t) - 1 . Our methods here are also available to the time decay issue of the complex fluid flows with partial dissipation. [ABSTRACT FROM AUTHOR]