The invention discloses a push-pull fast locking round connector, comprising a plug housing (1), an unlocking sleeve (2), a steel ball (3), an opening elastic closing ring (4) and a socket housing (6), wherein the unlocking sleeve (2) is sleeved at the outer side of the plug housing (1), the socket housing (6) stretches into an inner cavity of the plug housing (1), the sidewall of the inner cavity of the plug housing (1) is provided with a groove which is internally provided with the opening elastic closing ring (4), the groove is provided with an opening communicated with the outer side of the plug housing (1), the opening is internally provided with the steel ball (3), the steel ball (3) comes into contact with the opening elastic closing ring (4), the inner side of the unlocking sleeve (2) is provided with a protrusion part pressing the steel ball (3); a clamping slot is arranged the position, corresponding to opening elastic closing ring (4), of the outer side of the socket housing (6), and when the plug is locked with the socket, a part of the opening elastic closing ring (4) is positioned inside the groove and another part thereof is positioned inside the clamping slot. The push-pull fast locking round connector is reasonable in structure, saves space and can meet the demands of the product on fast locking, sealing and prevention of erroneous insertion.