Impoverished resources of ores and oil, together with the increased environmental regulations, provide the incentive for development and application of new materials and products compatible with the environment. There is still no adequate and complete solution for the disposal of composite waste. Energy recovery (incineration) is one the possible solutions, but fiber can not recover energy. It is possible to recycle the remains of fiber, but they have lower mechanical characteristics than the produced ones. Furthermore, the only economically justified recycling is for carbon fibers. One of the solutions would be to use natural reinforcements because they would burn along with the matrix. This paper describes some of the characteristics of natural reinforcements. Also described are organic polymers that can be used as resin in manufacturing of composites. The composite made of organic polymeric resin and natural reinforcement is called the green composite. Such compositions could be composted in special composts under certain conditions during which the process of composting would began. Besides the description of natural reinforcements and natural matrix the the properties of composites reinforced with linen fabric, were also explored and the properties of several samples of composites reinforced with glass and linen fiber combinations were compared. The purpose was to check the comparability of flax fibers with glass fibers.