<p>This work presents a concurrent topology optimization method for the multiscale design of fiber-reinforced composites. Under the moving morphable component (MMC) method framework, the fiber-winding angle at the microscopic scale and the geometric parameters of the macroscopic component are optimized as variables. A twined component model is proposed to design fiber-winding angles by adjusting macro-design variables. Structural responses from mono-scale and multiscale topology optimizations of fiber-reinforced composites are analyzed and compared. Numerical examples reveal a coupling effect between macroscopic topology and microscopic fiber distribution in multiscale optimization. The mean compliance is reduced by 30–40% compared to mono-scale optimization results, and the internal force distribution is explained in terms of fiber distribution at the micro level. The method is further applied to complex design domains and multi-load cases, closely resembling engineering applications. Multiscale topology optimization offers promising potential for uncovering novel macro–micro material layouts.</p>