OIL STRAINER OF TRANSMISSION

[Object] to provide an oil strainer which is simple in structure and with which it is possible to reduce the total amount of oil and to restrain aeration from being generated. [Solving means] In an oil strainer for a transmission including a resin-made upper case which is formed in a side surface of an upper part of a communication port for communication with a pump and which has an upper flange along the outer periphery thereof, a resin-made lower case which is provided with an oil suction port in a lower surface thereof and which has a lower flange joined to the upper flange of the upper case, and a filter member which is disposed in a space formed by joining the upper and lower cases and which filters an oil flowing from the oil suction port to the communication port, the oil strainer is configured to further includes an oil suction port cover member which is so formed as to cover at least an inside upper surface of the oil suction port and which forms a passage for conducting the oil to the filter member.