<p>This study presents an analysis of the integration of manufacturing constraints into a topology optimization algorithm for long fibre composite materials within a fully three-dimensional design domain. Constraints on minimum feature size, fibre parallelism, and minimum curvature radius have been incorporated into a topology optimization framework that combines a level-set method for material distribution with an evolutionary approach for determining fibre paths. A series of test cases has been developed to evaluate the influence of these orientation-based manufacturing constraints on the algorithm’s outcomes. A key contribution of this work is the implementation of manufacturing constraints in a fully three-dimensional context, where feasible fibre orientations are not restricted to predefined planes. As a result, fibre paths can follow arbitrary trajectories in 3D space. The results demonstrate that the proposed constraints effectively regulate the orientation field, ensuring the manufacturability of the component when the constraints are appropriately tailored. The study includes a concise literature review of prominent topology optimization algorithms and relevant manufacturing constraints for composite materials, a mathematical formulation of the proposed algorithm, and a comparative analysis of the effects of the selected constraints by contrasting constrained and unconstrained optimization results.</p>