The electrical power is a basic service for the communities’ development. In this research work the voltage harmonic distortion of the electrical network of Trujillo city – Peru has been assessed. The measurements of the total voltage harmonic distortion factor, THDV, were carried out with the TOPAS 1000 device, according to the rules stipulated in the Peruvian electrical services regulation, D. S. Nº 020-2001, which establishes a control period of seven days, in recording intervals of 10 minutes. The data collection was made in the low voltage side of the transformation stations known as common connection points (PAC). The measurements were made in the randomly chosen 117 and 152 PACs during the 12 months of the years 2004 and 2005, respectively. It was found that the first four harmonics dominants of the Trujillo electrical network are the fifth, seventh, third and second ones. Ta...