STRUT BEARING AND VEHICLE STRUT SUSPENSION

Provided is a strut bearing including an upper case and a lower case that are made of a synthetic resin, and an engaging portion for preventing separation of components which are free from any stress exerted thereon during assembly. The strut bearing includes an outwardly-projecting piece row on an inner diameter side of an upper case, and an inwardly-projecting piece row on an inner diameter side of a lower case. Within a relative pivoting range of the upper and lower cases in a use state of the strut bearing, a detachment preventing engagement portion for preventing the upper and lower cases from being separated from each other in the axial direction is provided. Within a predetermined angle range outside the relative pivoting range, the detachment preventing engagement portion is not present.