In this study, natural fiber reinforced polylactic acid composites have been developed by hot pressing through film-stacking procedure. The reinforcement materials used are nettle, Grewia optiva and sisal fibers in the plain weave form. For comparison purposes, polypropylene-based composites using the same fibers have also been developed. Mechanical properties (tensile, compressive, flexural, and impact properties) of all the developed composites have been evaluated through standard test procedures. It has been found that the polylactic acid based composites have superior mechanical properties and can be a potential substitute for traditional synthetic fiber composites in many application areas. Polylactic acid/sisal composite showed overall the best performance in terms of mechanical behavior. The morphological study of the fractured surface during mechanical testing has been done using scanning electron microscopy, which provides the mechanism of failure of composites during different types of mechanical loadings.