threaded joint for pipes, comprising: a pin component 3 including a male member 7, a nose portion 8 extending from the male member 7 toward a pipe end, and a shoulder portion 12 provided at an end of the nose portion 8; and a box component 1 including a female member 5 screwed onto the male member 7, an inner peripheral surface 30 facing an outer peripheral surface 20 of the pin nose or the nose portion 8 of the pin component 3, and a shoulder portion 14 that comes into contact with the shoulder portion 12 of the pin component 3, wherein the outer peripheral surface 20 of the pin nose 8 is a convex surface 20; the inner peripheral surface 30 of the box component 1 is a tapered surface 30 that interferences with the convex surface 20 of the pin nose 8 when joined with the pin component 3; the shoulder angle θ of the shoulder portions 12 and 14 is larger than or equal to 0°; the pin component 3 and the box component 1 are joined by the screwing to bring the convex surface 20 of the pin nose 8 and the tapered surface 30 of the box component 1 into metal-to-metal contact with each other, so that the contact interface thereof forms a sealing portion 40, characterized in that a box-side lip length L, which is the axial distance between a pin-nose-end corresponding point P of the box component 1 and a load surface 18b of a lip-side internal thread ridge 50 closest to the pin-nose-end corresponding point P, is 300 or more and 1,000 or less times as long as an insertion surface interval δ, which is the axial interval between an insertion surface 19b of an internal thread ridge at a position two or more ridges backwards from the lip-side internal thread ridge 50 and an insertion surface 19a of an external thread ridge facing the insertion surface 19b when tightened. a pin component 3 including a male member 7, a nose portion 8 extending from the male member 7 toward a pipe end, and a shoulder portion 12 provided at an end of the nose portion 8; and a box component 1 including a female member 5 screwed onto the male member 7, an inner peripheral surface 30 facing an outer peripheral surface 20 of the pin nose or the nose portion 8 of the pin component 3, and a shoulder portion 14 that comes into contact with the shoulder portion 12 of the pin component 3, wherein the outer peripheral surface 20 of the pin nose 8 is a convex surface 20; the inner peripheral surface 30 of the box component 1 is a tapered surface 30 that interferences with the convex surface 20 of the pin nose 8 when joined with the pin component 3; the shoulder angle θ of the shoulder portions 12 and 14 is larger than or equal to 0°; the pin component 3 and the box component 1 are joined by the screwing to bring the convex surface 20 of the pin nose 8 and the tapered surface 30 of the box component 1 into metal-to-metal contact with each other, so that the contact interface thereof forms a sealing portion 40, characterized in that a box-side lip length L, which is the axial distance between a pin-nose-end corresponding point P of the box component 1 and a load surface 18b of a lip-side internal thread ridge 50 closest to the pin-nose-end corresponding point P, is 300 or more and 1,000 or less times as long as an insertion surface interval δ, which is the axial interval between an insertion surface 19b of an internal thread ridge at a position two or more ridges backwards from the lip-side internal thread ridge 50 and an insertion surface 19a of an external thread ridge facing the insertion surface 19b when tightened.