An endoscope connector (41; 41A; 41B; 41C) connected to a pipe sleeve of an endoscope, the endoscope connector comprising (41; 41A; 41B; 41C): an outer cylinder member (51; 51A; 142) including an inflow port (61; 142a1) to which a fluid delivering apparatus is connected, an outflow port (62; 62A; 144b1) for feeding out fluid that flows in from the inflow port (61; 142a1), a channel that connects the inflow port (61; 142a1) and the outflow port (62; 62A; 144b1), and a first inner circumferential section (63a; 163a) provided on an inner side of the channel; an inner cylinder member (52; 144) including an advancing/retracting section (52a; 144) disposed to be capable of advancing and retracting along the channel and having an outer diameter smaller than an inner diameter of the first inner circumferential section (63a; 163a), and a through-path (65; 144d) that pierces through the advancing/retracting section (52a; 144) along the channel; an urging member (53; 154) disposed in the first inner circumferential section (63a; 163a) and configured to urge the inner cylinder member (52; 144) toward the outflow port (62; 62A; 144b1); and a watertight section (54; 156) disposed in an outer circumference of the advancing/retracting section (52a; 144) or in the first inner circumferential section (63a; 163a) and configured to fill a gap between the advancing/retracting section (52a; 144) and the first inner circumferential section (63a; 163a) when the advancing/retracting section (52a; 144) is disposed in the first inner circumferential section (63a; 163a), wherein the fluid introduced from the inflow port (61; 142a1) when the advancing/retracting section (52a; 144) and the first inner circumferential section (63a; 163a) are arranged side by side in a watertight manner sandwiching the watertight section (54; 156) is fed out passing through the through-path (65; 144d), characterized in that the outer cylinder member (51; 142) includes a second inner circumferential section (63b; 163b) provided further on the outflow port (62; 62A; 144b1) side than the first inner circumferential section (63a; 163a) and having an inner diameter larger than the inner diameter of the first inner circumferential section (63a; 163a); and when the inner cylinder member is present in the second inner circumferential section such that the watertight section (54; 156) is not sandwiched by the advancing/retracting section (52a; 144) and the first inner circumferential section (63a; 163a), the fluid introduced from the inflow port is fed out passing through the through-path (65; 144d) and a gap between the inner cylinder member (52; 144) and the second inner circumferential section (63b; 163b) of the outer cylinder member (51; 51A; 142). an outer cylinder member (51; 51A; 142) including an inflow port (61; 142a1) to which a fluid delivering apparatus is connected, an outflow port (62; 62A; 144b1) for feeding out fluid that flows in from the inflow port (61; 142a1), a channel that connects the inflow port (61; 142a1) and the outflow port (62; 62A; 144b1), and a first inner circumferential section (63a; 163a) provided on an inner side of the channel; an inner cylinder member (52; 144) including an advancing/retracting section (52a; 144) disposed to be capable of advancing and retracting along the channel and having an outer diameter smaller than an inner diameter of the first inner circumferential section (63a; 163a), and a through-path (65; 144d) that pierces through the advancing/retracting section (52a; 144) along the channel; an urging member (53; 154) disposed in the first inner circumferential section (63a; 163a) and configured to urge the inner cylinder member (52; 144) toward the outflow port (62; 62A; 144b1); and a watertight section (54; 156) disposed in an outer circumference of the advancing/retracting section (52a; 144) or in the first inner circumferential section (63a; 163a) and configured to fill a gap between the advancing/retracting section (52a; 144) and the first inner circumferential section (63a; 163a) when the advancing/retracting section (52a; 144) is disposed in the first inner circumferential section (63a; 163a), wherein the fluid introduced from the inflow port (61; 142a1) when the advancing/retracting section (52a; 144) and the first inner circumferential section (63a; 163a) are arranged side by side in a watertight manner sandwiching the watertight section (54; 156) is fed out passing through the through-path (65; 144d), characterized in that the outer cylinder member (51; 142) includes a second inner circumferential section (63b; 163b) provided further on the outflow port (62; 62A; 144b1) side than the first inner circumferential section (63a; 163a) and having an inner diameter larger than the inner diameter of the first inner circumferential section (63a; 163a); and when the inner cylinder member is present in the second inner circumferential section such that the watertight section (54; 156) is not sandwiched by the advancing/retracting section (52a; 144) and the first inner circumferential section (63a; 163a), the fluid introduced from the inflow port is fed out passing through the through-path (65; 144d) and a gap between the inner cylinder member (52; 144) and the second inner circumferential section (63b; 163b) of the outer cylinder member (51; 51A; 142).