To obtain a seamless brassiere capable of providing a good wearing feeling to a wearing parson, and supporting the breasts, further to provide a method for producing the seamless brassier, and to obtain a blank capable of being changed to the seamless brassier by a minimum processing step.

A cylindrical blank 30 is knitted by a circular knitting machine. The first and the second wale like opening parts are formed along the both sides of the blank 30 to form a body opening part 32 and a neck opening part 34. The terminal part of the blank forms an arm opening part 36 by cutting off a desired shape. Further, a belt like tape is attached to the each opening part of the body, the neck and the arms to complete the brassier.