This invention is to provide a hollow filament membrane module, the structure of which is excellent in the fluid-tightness, is strong in the bonding strength of a welding portion and is of high efficiency in manufacture.A hollow filament membrane module is comprised of: a hollow filament membrane bundle 4 a body case 3, for accommodating the hollow filament membrane bundle 4 a membrane fixing layer 5, for fixing the hollow filament membrane bundle 4 on the inner wall at an end portion of the body case 3 and headers 8,9, arranged respectively at opening end portions of the body case and having a mouth 6 for introducing liquid to be treated or a mouth 7 for discharging the treated liquid. The headers 8,9 and body case are welded by ultrasonic welding at least at two parts over the entire circumference thereof, that is, a shear joint is used as a kind of joint design for welding a side face of the outer periphery of the body case to the inner side face of each header over the entire circumference thereof and a butt joint is used as a kind of joint design for welding an end face of the body case to the inner side surface of each header over the entire circumference thereof.本發明提供一種具備液密性優良、熔接部分的接合強度高且可高效率生產的構造之中空絲膜模組。其具備:中空絲膜束4;本體外殼3,收納前述中空絲膜束4;膜固定層5,用於將前述中空絲膜束4固定在本體外殼端部的內壁;及頂蓋8、9,安裝於外殼開口端部且具有被處理液的導入口6或導出口7。前述頂蓋8、9與本體外殼3在整個周圍至少2處區域以超音波熔接,其中使用剪力接頭作為在整個周面超音波熔接本體外殼外周的側面與頂蓋的內側面之接頭設計,並使用對接接頭作為在整個周面超音波熔接本體外殼的端面與頂蓋的內側面之接頭設計。3‧‧‧本體外殼4a‧‧‧中空絲膜5‧‧‧膜固定層9‧‧‧頂蓋10a‧‧‧剪力接頭的超音波熔接部10b‧‧‧對接接頭的超音波熔接部11‧‧‧樹脂貯存部12‧‧‧樹脂貯存部
