A printed circuit board (PCB) having an improved waterproof structure for preventing corrosion of a substrate is disclosed. A plurality of screen-printed protrusions is provided at the PCB surface. The plurality of protrusions allow water to be formed in waterdrops so that the waterdrops can flow to the outside of the PCB. The PCB is arranged to have a tilted structure for facilitating discharge of the water. The tilted structure discharges waterdrops to a lower side of the PCB. The PCB and a PCB assembly having the same are applicable to electronic appliances such as a washing machine.