The work is aimed to increase mechanical properties of polymers produced by laser stereolithography technology by modifying the composition of photocurable resin (PCR) by highly dispersed filler. A resin based on vinyl ester was developed as an initial one, and aluminum hydroxide was chosen as a filler for it. Adding the filler to the initial PCR leads to a marked increase in the viscosity of the composition at 25 °C. For comparison samples obtained both by laser stereolithography technology and at initiation of polymerization by incoherent UV radiation were simultaneously studied. Thermomechanical analysis of the samples was carried out and the samples were studied by differential scanning calorimetry to determine the thermomechanical characteristics and the degree of conversion of double bonds for these samples. It has been confirmed that the post-treatment of the samples is a necessary step in achieving their high mechanical properties. It is shown that the use of aluminum hydroxide as a FPC filler leads to an increase in the physical-mechanical and thermomechanical properties of cured samples.