To provide a spacer for a cross roller bearing which is easy to machine and handle without degradation of strength, and which suitably maintains oil lubrication and suppresses heat generation without mix of dust or the like.

The spacer 1 located between rollers 18 of the cross roller bearing 11 arranged so that adjacent roller axial lines La, Lb become approximately at a right angle, is in an approximately short cylinder shape formed of synthetic resin having a self-lubricating property, and is provided with a roller contacting recessed part 4 crossing mutually with both end surfaces 2a, 2b of an approximately short cylinder main body 2 at an approximately right angle, roller contacting surface oil reservoir grooves 5a, 5b provided on the roller contacting recessed part, an outer circumferential end surface part 7 formed on a side of an inner ring 12 of an outer circumference part 6 of the short cylinder main body, and an outer circumferential oil reservoir groove 8 formed on the outer circumference part and reaching to the outer circumferential end surface part, and at least one 5a of the roller contacting surface oil reservoir grooves is opened on the outer circumferential end surface part.