Up to date, there are no evident research works carried out to improve and verify the physical, mechanical, barrier and damping properties of bioelastomer composites with addition of straw. Moreover, the problem of improving the reuse of straw is now demanding attention in the major cereal-growing areas of the world. The aim of this study was to receive knowledge of characteristic and producing multifunctional elastomer biocomposite filled with straw. Rye, oat and triticale were found to be active fillers improving wide range of rubber composites functional properties like: static mechanical, damping, barrier properties and hardness. The use of straw as a filler also increased cross-linking density. Dynamic-mechanical analysis indicates the presence of strongly developed secondary structure of examined fillers in vulcanizates. Moreover, all of the vulcanizates proved to be resistant to thermo-oxidative degradation. The application of straw as a filler allowed obtaining composites with lower value of oxygen index, that reflecting higher tendency of smoke generation. Introducing the straw into polymer matrix reduced the manufacturing costs of composites through the use of a significant amount of inexpensive and renewable filler. Furthermore straw fillers modify natural rubber, obtaining high-performance materials with meaningly enhanced applications.