To provide a double row tapered roller bearing unit having favorable assembly accuracy and easy machining, and capable of easily carrying out pre-load control and pre-load readjustment.

An inner ring spacer 60 is held between a pair of inner side inner ring elements 24, and both outer side inner ring elements 14, 14 are pressed from both axial sides by presser rings 31 attached to an outward flange-like collar part 30 formed on an outer peripheral surface of one end of axial both ends of an inner side outer ring member 22 and the other end, or alternatively, by a pair of presser rings 31 attached to axial both ends of the inner side outer ring member 22.