Port and port assembly for use with tool for minimally invasive surgery, and method of using same port and port assembly

PURPOSE: A port and a port assembly are provided to easily insert minimally invasive surgery tool through cannula by using a soft stopper. CONSTITUTION: A port(100) comprises a main body(200) and a cannular insertion part(300). A plurality of insertion grooves are formed in the outer surface of the main body with a predetermined interval. The insertion hole has a right-angled triangle cross section. The cannular insertion part is arranged in the inner part of the main body. The cannular insertion part comprises the insertion main body and a plurality of cannulars. At least one among a plurality of cannulars is sloped with a predetermined angel to at least two parallel cannulars. A gas supply pipe is arranged in one among a plurality of cannulars.