In Colombia, the industry of the plastic has been characterized to de the manufacturer activity more dynamic of the last three decades, however, the processing of plastic pieces is carried out with not very appropriate technologies to guarantee production with better characteristics; this is related with the design, operation and control of the equipment installed in the companies. This article describes the implementation of a control system by means of programmable logical controller in an injector of plastic of a fitting plant, oriented to the improvement of the productivity through the reduction of the time of production, to the increase of quality of the product and the decrease of costs, with the purpose of contributing to the profitability of the process and the consolidation of the company in the sector.