To provide a valve body assembly for an automatic transmission, allowing intuitive determination of the existence or not of a filter of a gasket by reducing a layout space for assembling error discrimination while eliminating the possibility of assembling a gasket with no filter in error for a gasket with a filter.

Tabs 30a, 40a, 13a are provided on a first gasket 30, a second gasket 40 and a separate plate 13, at one position on the same site of each. Opening holes 30b, 40b, 13b are formed in the tabs 30a, 40a, 13a, respectively, and the filter 31 is provided only in the opening hole 30b of the first gasket 30. Thus, the existence of the first gasket 30 is accurately discriminated and the existence of the second gasket 40 and the separate plate 13 is also identified.