To make a cleaning tank of cleaning equipment, in its turn, an outer size of the cleaning equipment compact by enabling the number of times for cleaning to be taken more than conventionally until from one time charging of a cleaning liquid a necessity for exchanging the whole cleaning liquid appears.

In ultrasonic cleaning equipment having a cleaning tank 3 capable of dipping the whole metal mask, a container 1 containing a cleaning liquid, and a cleaning liquid circulating system so constituted that the cleaning liquid can be sent out from the container 1 to the cleaning tank 3, and the cleaning liquid stored in the cleaning tank 3 can be returned to the container 1, a cleaning liquid return opening in the container 1 is so constituted that a filter can be attached and detached, the filter is so constituted that a coil spring is convered by a bag comprising a filter material, and so constituted that the filter can be attached to and detached from the cleaning liquid return opening by use of expansion and contraction of the coil spring.