In this work, are presented the results obtained in the production of porous silicon (SP) type p with resistivity of 0,1 Um, using a pulsed laser that it emits in three wavelenghts, 1064, 532 and 355 nm, with energies of 900mJ, 450mJ, and 200mJ respectively, with frequency repetition pulse of 10 Hz and with emission times of 6 ns, 5ns respectively. The pore size has been determined in function of exposure time on the silicon wafer of the radiation laser, simultaneously to the three wavelengths. The characterization of the pore size has been carried out by Scanning Electronic Microscopy (SEM), with which we determine that the SP has a spherical micro-structure with pore size in the order of micron.