A new oil producing system is proposed which consists of a group of underwater wells, an underwater riser and a floating storage facility for the production of the wells. The group of wells and the riser are interconnected through a manifold system in such a way that the production from any well or from the entire group of wells go to the base (foundation) of the riser. From above the riser is connected with the floating storage facility which is equipped, besides tanks for storing the well products, with a separation device for separating the oil and the accompanying gas. The gas is used as a fuel for producing electric power required by the dynamic positioning systems. The products from each well are tested by means of a regulable coupling controlled by means of a cable, which is passed from the surface through the riser. The wellhead equipment for the unslanted wells is mounted on a template previously installed on the sea floor. From the template the well products enter the riser through the manifold unit system.