A laser-based method for local monitoring of diamond nucleation centers densities is presented. The method uses a pulse ruby laser to suppress the native nucleation centers on silicon wafers due to local surface melting and/or to create the dense diamond nucleation by implantation of highly dispersive diamond particles. Nucleation densities of 10(12) cm(-2) were reached with this method on definite substrate regions by using nontransparent masks. The effective prevention of a diamond growth with the chemical vapor deposition process was obtained on the substrate surface treated by the laser.