Untreated air-cooled Oil Shale Heat carrier retorting waste ash (SHC) was ground, sieved into different mesh sizes and introduced into LLDPE matrix.Compounding was performed via simple laboratory kneader and gravimetric fed co-rotating, twin-screw compounder. In carrent work rheological and mechanical behavior of PE/SHC compounds are discussed. Oil Shale heat carrier retorting ash (SHC) is byproduct of oil shale industry and is oxide rich carbom black material [1] It was studied as potential functional filler in thermoplastics ( i.e. PE, PP).That is because SHC consist multi-oxides that could offer potential property enhancement and could lower consumption of naturally extracted mineral filler. Compounding of PE and PP with SHC was performed at mass temperature 180C. For SHC average particle sizes of 71; 40 and 20 ϻm and amounts of 10; 20; 30 w.% were tested. Compounded materials were formed into samples for rheological testing (shear-viscosity) and mechanical testing. Sher viscosity values for the composites were slightly higher than values for neat PE and PP but insignificant influences were wickened when varying filler parameters. SHC increased tensile modulus but decreased tensile strength and elongation at break. The reason could be filler matrix interfacial debonding which needs compatibilities agents - longtaile References:1. Sedman A Talviste P.; Mõtlep R. Geology131-132 37-44; 2012