In this study, conductive and transparent polycaprolactone (PCL)/carbon black (CB) nanofibers are produced by electrospinning. In order to investigate the effect of solvent system on the optoelectrical properties of PCL/CB nanofibers, the fibers are produced from two different solvent systems; namely, chloroform (CHL) and dimetyl formamid (DMF). For optoelectrical characterization, nanofibers are produced with different deposition times in the range of 1–10 minutes. Surface, optical, electrical and optoelectrical properties of the PCL/CB nanofibers are evaluated. Nanofibers produced from CHL solvent system results in non-uniform nanofibers with higher diameters. They also give a larger diameter distribution. On the other hand, nanofibers with uniform and smaller diameters are obtained from DMF system. UV-spectrophotometer analysis show that nanofiber mats produced from both solvent systems have similar optical transparencies. Lower sheet resistance values are obtained with the nanofiber mats produced from DMF system according to electrical characterizations. Higher Figure of Merit values are calculated for the nanofiber mats produced in DMF solvent system. Considering all the results, it can be concluded that PCL/CB nanofibers produced from DMF solvent system are better candidates compared to the nanofibers produced from CHL solvent system for optoelectrical applications.