An adhesive tape dispenser having a guide function includes a handle, a retaining frame, a tape cutting unit, a guide unit, and a tape holding unit. The retaining frame is disposed on the handle. The retaining frame has a pair of vertical plates. The tape cutting unit has a roller and a blade that are located between the vertical plates. The guide unit has a pair of guide plates located outside the respective vertical plates. The guide plates each have a fastener for securing the guide plates to the respective vertical plates. The tape holding unit is configured to install an adhesive tape roll. Guide members of the guide plates are able to be in close contact with both sides of wooden planks, so as to achieve the effect of sticking the adhesive tape centrally.