Toxicological studies are urgently needed to confirm the safety of Sophora japonica extracts for clinical use. In particular, in addition to pharmacy and pharmacology, phytotherapy, herbal medication, Sophora japonica extracts are widely used as biologically active supplements. Scientfic data suggests that some of Sophora japonica extract components have very comprehensive biological effects. In the present study, our hypothesis assumed the potential reprotoxicity of Sophora japonica extract in respect to mouse germ cells (GC-1 spg, GC-2 spd) in vitro. Specifically, we were interested in the high-performance liquid chromatography (HPLC) identification of extract components and its stress-related effects on cellular and biochemical features, such as mitochondrial metabolism, cell cycle progression, oxidative stress balance and micronuclei formation. The results indicate that Sophora japonica extract induces oxidative/nitrosative stress-mediated impairment of the mechanism for free radicals scavenging, which may provoke genotoxic events in germ cells, by cell cycle arrest and micronuclei formation. Therefore, the interplay between reactive oxygen species (ROS)/reactive nitrogen species (RNS) and antioxidant system is critical for normal testicular function maintenance in the their environment. The specific pathways and mechanisms involved in the reprotoxicity of Sophora japonica need to be further investigated.