Currently, the regulation of humidity in the process of drying fishmeal with only the manual adjustment of its operating parameters is difficult to achieve. This is due to the complex dynamics of the process and sensitivity to sudden changes in certain variables, such as the input product from the previous process (pressing), causing quality deviations that are reflected in the percentage of humidity in the final product. This represents a higher cost of production, since the product without the ideal humidity must be reprocessed. This paper presents the development of a system of control and monitoring online, carrying out a procedure of identification of the process of drying fishmeal for the design of a PI control that regulates the temperature of the fishmeal at the exit of the dryer. This system was installed in one of the rotatube dryers of Pesquera Diamante S.A. (Lima-Callao-Peru). Different tests were carried out in the plant, achieving a temperature control of the fishmeal at the dryer outlet. The implementation of this system guarantees a better operation in the management of the drying process, decreasing the operation time to stabilize the dryer in case of an unexpected disturbance, which leads as a consequence to a reduction of reprocessed fishmeal, which finally translates into a reduction of production costs.