This invention provides a connector which can easily and certainly break through a film sealing a port portion in spite of the thickness of a connecting portion of the film, and which can be inserted into a container and communicated with each other. A connector (30) of this invention has a base portion (33) rotated around an axis (L1) and attached to a port portion (12) of a container (10), a first connecting portion (31) disposed on one end side of the base portion (33) for breaking through a film (16) sealing a port portion and inserted into the container (10), and a second connecting portion (32) disposed on the other end side of the base portion (33) for connecting another instrument (20), wherein by inserting the first connecting portion (31) into the container (10) and connecting another instrument (20) to the second connecting portion (32), the container (10) and another instrument (20) are communicated each other through the first connecting portion (31) and the second connecting portion (32) so that can flow through the content of the container (10) or another instrument (20). The first connecting portion (31) has a cylindrical portion (35), a tip portion 35a of the cylindrical portion (35) at which disposed with a stepped-shaped stabbing portion (36) with a sharped top portion (36a). By stabbing the stabbing portion (36) and rotated it together with the base portion (33), the film (16) is cut to form an opening and the cylindrical portion (35) is inserted into the opening.本發明係提供一種連接器,無論刺破密閉通口部之薄膜之連接部的粗細為何都可容易且確實地刺破薄膜,且可確實地插入於容器內而使其連通。本發明之連接器30係具備:基部33,係繞著軸線L1轉動而裝設於容器10的通口部12;第一連接部31,係設於基部33的一端側以刺破密閉通口部12的薄膜16而插入於容器10內;及第二連接部32,係設於基部33的另一端側,供其他器具20連接;其中,第一連接部31插入於容器10內,並且在第二連接部32連接有其他器具20,從而以使容器10或其他器具20之收容物可經由第一連接部31及第二連接部32而流通之方式連通容器10與其他器具20之間;該連接器30係構成為:第一連接部31係具備筒部35;在筒部35的前端部35a,係具有使頂部36尖突而形成之段差形狀的刺穿部36;藉由將刺穿部36進行刺穿且使其隨同基部33一起轉動,使得薄膜16被切斷而形成開口,並且使筒部35插入於開口。