PURPOSE: To omit the rubber ring for preventing the grout leak of a concrete material fitted to the outer periphery of a joint collar at the time of the molding of a Hume concrete pipe.

CONSTITUTION: A joint collar 10 forms a ring-shaped diameter expanding part 21 whose diameter is larger than the inner diameter of a form 20 in a clamped state on the base end part 16 fixed to the pipe end of a Hume concrete pipe 15. A casting is attached to the end part of the form 20 formed into an almost cylindrical shape and the form 20 is clamped to bring the diameter expanding part 21 into contact with the inner surface of the from 20 under pressure. A concrete material is injected in the form 20 having castings 24, 26 attached to both ends thereof and subjected to centrifugal molding to produce the Hume concrete pipe 15 having the base end part 16 of the joint collar 10 fixed to the pipe end thereof. Therefore, the joint collar can be easily attached to the form and the number of the production processes of the joint collar can be reduced. No difference in level is generated between the Hume concrete pipe and the end part of the joint collar.