This article shows the methodology used to evaluate the linear and non-linear effects present in a radio over fiber system (RoF) by employing the multiplexing technique used for dense wave division, the Dense Wavelength Division Multiplexing (DWDM) technique. It is completed with a dissemination of 50 GHz, in accordance to the standards of the International Telecommunication Union (ITU), through a channel speed of 10 Gbps, at an input power in the optical channel of 30mW, for optical fiber stretches of 40km, 60km and 80km. It presents the modeling of the RoF system graphically through a block diagram by means Matlab, a computational tool, whereby each of the stages of the RoF system are implemented using the libraries offered by the ‘simulink’  toolbox of Matlab. As a result, it is obtained that the methodology proposed for the evaluation of the RoF system using the DWDM technique allows for the analysis of linear and non-linear effects; where it is observed that the effects that degrade the signal are proportional to the established distances of the optical fiber and that the optical input power used is optimal for the optical fiber to behave as a non-linear medium.