A coupling for fluid-tight connection of two fluid-guiding portions in medical applications. The coupling is an axially lockable quick-connect coupling and comprises a male coupling portion having a continuous first passage and a female coupling portion adapted to be slipped over the male coupling portion and having a continuous second passage. A preferably circumferential radial sealing is provided on the outer periphery of the male coupling portion and/or on the inner periphery of the female coupling portion.