The paper analyzes the tensile behavior of some new biocomposite materials based on polypropylene reinforced with hemp shives for different volume fractions and sizes. The aim of this study is to make a comparison between the tensile properties of these materials and to determine in which way the values of the tensile strength and tensile modulus are influenced by the volume fraction and dimensions of the reinforcement elements. The analyzed materials are new materials based on renewable and recyclable resources and from this point of view these materials have a less harmful impact on the environment compared to the conventional composites. By analyzing the tensile properties of polyproylene based biocomposites reinforced with hemp shives it can be observed in which way these materials could replace conventional materials in various fields of applications.