In recent years, biopolymers have increasingly become the focus of scientific attention. The aim is to replace conventional polymers with bio-based and/or biodegradable polymers. One of the most promising biopolymers is polylactide acid (PLA). Polylactic acids are characterized, among other things, by high strength, contour fidelity and compostability. However, PLA also has disadvantages such as low heat resistance, high brittleness, slow crystallization and rapid aging. Due to the low crystallization rate, cycle times in the injection molding process increase significantly. Therefore amorphous injection molded parts are usually taken. However, these do not have a high heat resistance. In order to increase the degree of crystallization while shortening the cycle times, we have focused in this work on the study of the influence of various processing parameters on the morphology and mechanical properties. For this purpose, different PLA grades were injection molded at different mold temperatures, melt temperatures and holding times. The injection molded parts were examined by thermal analysis to evaluate the degree of crystallinity, by optical microscopy combined with hot stage experiments to visualize the morphology, and by mechanical testing to characterize the mechanical properties. It has been shown that the degree of crystallinity increases with increasing mold and melt temperature as well as with increasing holding time. However, no correlations to crystallinity could be found for the mechanical properties, e.g. Young's modulus.