An access port is fixed to a biological membrane, such as a pericardium, in a state in which it penetrates the biological membrane. Provided is an access port (1) including a tubular member (2) having a through-hole (2a) passing therethrough in an axial direction, a needle-like member (3) having a tip (3c) pointing toward a rear end of the tubular member (2) and mounted to an outer surface of the tubular member (2), and a manipulating means (4) for switching between a state in which the tip (3c) is projected and a state in which it is not projected.