The utility model provides a concentric double -barrelled water injection well lower seal ware should seal the ware in the pit and include: close seal barrel and intubate, close seal barrel and big oil pipe are connected, and the intubate is connected with little oil pipe, and close seal barrel is the column hollow cylinder, sets up seal assembly in the hollow cylinder, and seal assembly follows close seal barrel axial extending direction and have the through -hole, and the intubate through sealing between seal assembly and the intubate, realizes sealing of close seal barrel and intubate in inserting seal assembly's through -hole to realize that big oil pipe and little oil pipe's is sealed.