To provide an inexpensive and small, particularly very thin, bearing unit and its manufacturing method, capable of not just preventing leaking of viscous fluid but also reducing the number of parts.

The bearing unit 30A is composed by forming a shaft insertion hole 33a piercing a center part, and directly forming at least one communication passage 50A facing the shaft insertion hole 33a between an outer surface of a radial bearing 33 formed with dynamic pressure generating grooves 43, 44 on an inner circumference face 33b of the shaft insertion hole 33a, and a resin housing 37A formed by outsert forming. Its manufacturing method is indicated in Figure 4 and Figure 5.