The present work proposes an electronic equipment oriented to insulin dosage with automatic control of the filling process in a syringe, using digital image processing. The equipment aim to improve the precision of the dosage, which is often carried out manually and inaccurately. The proposed system is made up of a mechanical part composed of endless screw, couplers and steppers motors. This allows the plunger of the syringe to be vertically moved and the container containing insulin punctured. It also presents a camera for the acquisition of images and an algorithm implemented in a reduced-board computer. The algorithm detects the level of filling by image processing and determines if the amount of insulin is appropriate according to the data entered by the user. The stages of processing involve thresholding, averaging filtering, detection of the syringe plunger and determination of the filling level by contrast and intensity change. The validation of the equipment was made from the absolute error of the filling volume achieving an average absolute error of 0.00106ml with respect to the indicated value.