A composite sheet comprises a hydrophobic first plastic film layer forming an upper surface of the sheet, a second plastic film layer forming a lower surface of the sheet and a hydrophobic intermediate fibrous assembly layer disposed between these two layers. The first plastic film layer includes a plurality of first plane regions spaced one from another and extending parallel one to another in one direction and sawtooth-shaped first rising regions formed along edges of the first plane regions and the second plastic film layer includes a plurality of second plane regions. Such composite sheet is breathable but liquid-resistant and suitable for use for disposable garments.