To provide a bearing device with a sealing device having improved sealing performance for preventing the leakage of base oil from grease inside a bearing to the outside, and to provide its manufacturing method.

The manufacturing method is provided for the bearing device with the sealing device having a seal case 22 which has a cylindrical fixed portion 23 inserted and fixed into the inner periphery side of an end 11a of an outer ring 11, and a holding portion 24 extending from the fixed portion 23 to the outside of the outer ring 11 for holding a seal member to seal a space between inner and outer rings. It comprises a step of applying highly permeable adhesive 40 capsulated with a pressure-breakable film 42 to the outer peripheral face of the fixed portion 23 of the seal case 22, a step of inserting the fixed portion 23 to which the adhesive 40 is applied, into the inner periphery side of the end 11a, and a step of pressing the outer peripheral face of the fixed portion 23 against the inner peripheral face of the end 11a to break the film 42 of the adhesive 40 applied to the outer peripheral face of the fixed portion 23 and adhering the fixed portion 23 to the end 11a with the adhesive oozed from the film 42.