Polycrystalline Cu2FeSnS4 materials (abbreviated CFTS) were synthesized by a hydrothermal route implementing a one-step thermal treatment to measure dependence on different reaction times in the stabilization and structural, vibrational, and optoelectronic properties. The structural results have shown a tetragonal system with I-42m spatial group. The vibrational analysis by Raman spectroscopy allowed the identification of additional crystal phases arising from the synthesis procedure and corroborated the presence of a stannite phase. This evaluation showed that the reaction time gave the proposed synthesis procedure, significantly affects the semiconductor behavior of the solids; consequently, the conductivity measurements evidence a decrease from 1.02x106 to 9.84x105 W at 573 K as the synthesis time increases. These results described above, corroborated that the control of the reaction time provide a tool to successful fine-tune of the structural and conductivity properties of CFTS materials.