An airless sprayer is disclosed. A power sprayer equipped with an electromagnetic operated mechanism is easy in handling and simple in operation. However, in taking out a nozzle head, a piston pump and the like for the purpose of cleaning, it is very difficult to take them out and cumbersome to do so. Assembling is not easy. Taking-out operation and assembling operation of the nozzle head, the piston pump and the like can be accomplished easily whereby cleaning can be easily accomplished. The power sprayer of this kind can be used more conveniently.