The goal of this articles is to present a large assortment of methods of forensic science to investigate criminality in the banking and nonbanking domain. Nearly eight years ago in the banking system of Republic of Moldova, have taken place a scandalous event in the banking sector what is known as ”the banking fraud”. This event has shaken all civil society. Although this event shook society, the banking fraud until present is not discovered. In the reality, to achieve the aim of investigation is very difficult because banking criminal cases have a tremendous peculiarity – financial systemic complexity. Meanwhile in this item I have established a classical and fundamental methods from forensic science for criminal investigation body to realize specific objectives to figure out who is final gainer in the simple illegal banking loan.