Electronic Journal of Differential Equations, Vol. 2025 (2025), No. 58, pp. 1-29 Title: Global unique solution for 3D incompressible inhomogeneous magneto-micropolar equations with discontinuous density Authors: Xiao Song (Shandong Univ. of Technology, Zibo Shandong, China) Chenhua Wang (Shandong Univ. of Technology, Zibo Shandong, China) Xiaojie Wang (Shandong Univ. of Technology, Zibo Shandong, China) Fuyi Xu (Shandong Univ. of Technology, Zibo Shandong, China) Abstract: This article concerns the Cauchy problem of the incompressible inhomogeneous magneto-micropolar equations in $\mathbb{R}^3$. We first prove the global solvability of the model when the initial density is bounded from above and below with positive constants and the initial velocity, angular velocity, and magnetic field in a critical Besov spaces are sufficiently small. Then we obtain the Lipschitz regularity for the fluid velocity, magnetic field, and angular velocity by exploiting some extra time-weighted energy estimates. We show the uniqueness of the constructed global solutions by the duality approach. Submitted December 22, 2024. Published June 02, 2025. Math Subject Classifications: 35Q35, 35A01, 35A02. Key Words: Discontinuous density; global well-posedness; critical Besov space; magneto-micropolar equation.