Abstract: A non-dripping suck-back nozzle has a shell comprising a press cover (1), a revolving cover (2) and a cylinder (7). A needle valve (6) comprises a round rod (61) and a convex ring (62). The upper part of the round rod (61) of the needle valve (6) passes through an inner round pole (51) of a piston (5) and extends into a hollow channel (41) of a connecting bar (4). The round rod (61) and the connecting bar (4) are locked by each other. A channel is formed between the round rod (61) and the connecting bar (4). A space is formed between the round rod (61) and the inner round pole (51) of the piston (5).