A possible mechanism of complex formation between bacterial luciferase and NADPH:FMN-oxidoreductase from Vibrio harveyi sustained by electrostatic forces is studied. The complex between the enzymes is important for a direct FMNH₂ transfer without a contact with solvent, which could cause a rapid autooxidation and the formation of reactive oxygen species. In the current work the diversity of possible relative positions of NADPH:FMN-oxidoreductase and luciferase was obtained with Monte-Carlo sampling governed by oxidoreductase internal charged groups and electrostatic field caused by luciferase. Among the structures with the minimal energies, the one was found that has a proper active sites orientation for a direct FMNH₂ transfer. Possible role of hydrogen bonding between Arg291 and Gln197 of luciferase and oxidoreductase, respectively, in stabilization of this complex is proposed.