Crystallization of ultra-high-molecular-weight-polyethylene [UHMW-PE) filled solutions and gels was studied by differential scanning calorimetry. It has been found that the structure and properties of the gelating systems depend on solvent type, polymer concentration, and filler. Crystallization rate decreases as the polymer content is increased. The crystallization rate dependence on filler concentration passes through a maximum. The influence of a disperse filler on the structure, the stress-strain and relaxation properties of UHMW-PE gels has been studied. The results demonstrate the advantage of using less thermodynamically active solvents (thermodynamic activity means polymer-solvent interaction]. This gel-technology enables us to obtain UHMW-PE based materials with a 90-vol% content of iron particles. Highly loaded fibers based on UHMW-PE were obtained with a tensile strength of 40-50 MPa and an elastic modulus of 350-400 MPa.