A wet / dry type vacuum cleaner has a suction generator, a cleaner body including the suction generator at one side of a lower portion, an intake port being connected with a nozzle that is movable along a surface to be cleaned, and a discharge port through which a clean air is discharged, a contaminant separator removably mounted in the cleaner body to separate contaminant-laden wet air drawn through the intake port into the contaminant and water components and air, and then to store the separated contaminant and water therein, a cover, being open and closed, disposed on an upper portion of the cleaner body to seal an upper opening of the cleaner body, and a discharge path opening a fluid communication between the contaminant separator and the discharge port, for the air separated at the contaminant separating means to be discharged out through the discharge port of the cleaner body. Since the suction generator is provided at the lower portion of the cleaner body instead of the upper portion, the cover can be constructed in a simple manner and a user can remove the contaminant receptacle by simply opening the cover and emptying the contaminant receptacle.