The invention relates to a connector, in particular relates to an underwater oil collecting tree connector with a hydraulic drive. The connector comprises a connector shell, a fixed tray, a mobile tray, a top end cover and a bottom end cover, the top of the connector shell is fixedly provided with the top end cover; the bottom of the connector shell is fixedly provided with the bottom end cover; the fixed tray is fixedly arranged on the bottom of the top end cover in the connector shell, the mobile tray is arranged in a sleeving mode on the bottom end cover below the fixed tray. The connector is simple in structure and reliable in connection; through the mobile tray driving the clamping claw to move, the connector is made to engage with a well device, thus achieving the sealed connection between the connector and the well device, the whole connection process is simple and precise in movement, and solves the problem of the seal failures caused by the stress and strain produced by the seal piece following the operations between the underwater environment and the inner holes in the existing connector. The connector is particularly suitable for use in the quick connection of the vertical pipe and the underwater oil collection tree in the ocean drilling process.