Silica is not an essential component in the bonding system in XNBR-jute fiber systems. Mechanical anisotropy is observable only at the higher fiber loadings (40 phr and above) in XNBR-jute fiber composites. In composites containing sufficient amounts of bonding agent and fibers for tensile-strength anisotropy to be observed, tensile failure occurs by both fiber breakage and debonding. Fibers increase the aging resistance of XNBR composites. Mill shrinkage and green strength of XNBR improve, while Mooney viscosity increases and scorch time decreases with the addition of jute fiber to XNBR.