Abstract: A water-guide device in a tap, which includes an outlet connector with a circular plate, being mounted on the water outlet of a tap; the circular plate of the outlet connector is mounted on a positioning seat by means of a bubble head; the other end of the outlet connector is formed into a cylindrical part to be connected together with a guide pipe; the guide pipe extends through a passage of the body portion of the tap, and to the outer end of a concave seat of the water inlet; the guide pipe is connected with a snap connector having a partitioning ring, and then is connected with a water valve seat. The guide assembly can provide an isolation structure between the water valve seat and the bubble head so as to prevent water stream containing heavy lead from contact with the tap, i.e., to avoid lead being dissolved into water to jeopardize.