The invention discloses a double-line mutual-pouring ship lock with one shared storage reservoir and a mutual-pouring flow path. The shared storage reservoir (3) is arranged on one side of a left-lineship lock (1) and a right-line ship lock (2), a lock wall (15) is arranged between the left-line ship lock (1) and the right-line ship lock (2), a first sluice valve (1.1) and a second sluice valve (1.2) are arranged in the lock wall (15), a left-line ship lock forked gallery (5) communicating with the left-line ship lock (1) is arranged below the lock wall (15), a right-line ship lock forked gallery (6) communicating with the right-line ship lock (2) is arranged below the lock wall (15), and the first sluice valve (1.1) is located in the left-line ship lock forked gallery (5). The defects that in the prior art, a ship lock is provided with multiple stages of storage reservoirs, cost is high, and the ship lock is strictly limited by the pivot site condition are overcome, and the double-line mutual-pouring ship lock has the advantage that the ship lock water saving rate is improved by over 50%.