It is a common knowledge that the most promising way of scrap tires reuse is in combination with polymer binder and production of composite materials [1-3]. The authors have previously conducted studies of composition and technology of manufacturing composite material using mechanically grinded scrap tires and polyurethane type binder . It was found that mechanical properties of the composite material are highly dependent not only on the composition of material and the type of polymer binder used, but also on specific technological parameters such as moulding pressure, formation time, relative air humidity, temperature etc. [4-6]. The objective of this paper is to additional investigation of selected properties of the composite material based on scrap tires and polyurethane type polymer binder with defined reactivity (–NCO group content 2.4%) under specific circumstances , potentialy affecting polymer binder and therefore composite material properties, - water content in the rubber crumb. It is well known [7] that environmental moisture content directly affects the hardening degree of polyurethane polymers, conataining isocyanate gruops ,due to degree of change of polymer crosslinking. The Shore C hardness (ISO 7619, ISO 868), apparent density AD (LVS EN 1602), compressive stress at 10% deformation σ10 and compression modulus of elasticity E (EN 826) in correlation with the composition (wt.%) of composite material were investigated. Special attention was turned to investigation of volume components of the composite material, with different content of the polymer binder and presence of water in rubber crumb.