A duplexer module that prevents degradation of isolation between signal lines includes transmission filters, reception filters, phase adjusting circuits, and a multilayer substrate. The transmission filters and the reception filters are constituted as separate discrete components. The multilayer substrate includes filter mount terminals to which the transmission filters are mounted, and filter mount terminals to which the reception filters are mounted. The filter mount terminals are arranged along an upper side of the multilayer substrate, and the filter mount terminals are arranged along a lower side of the multilayer substrate.