The invention relates to an agricultural sprayer valve unit. An electronically controlled control valve and a passive overflow valve serially connected in fluid communication are arranged in the agricultural sprayer valve unit between a primary line and a secondary line. The agricultural sprayer valve unit may be used for any agricultural sprayer valve device, in particular in connection with the discharge of a fluid such as water, a fertilizer, an insecticide, a weedkiller and the like in agricultural or fruit or vegetable cultivation.