PURPOSE: To provide a bicycle deraillure which enables the direction of a chain guide to cope with the running direction of a chain installed on one sprocket out of a multi-sprocket means in a simple constitution.

CONSTITUTION: This invention is concerned with the bicycle delayer equipped with an inner link and an outer link 11 which are connected to a base member 9 in such a way as to be freely rocked via first pin 13 and a second pin 14, and with a link mechanism which is connected to the aforesaid inner and outer links 11 in such a way as to be freely rocked via a third pin 15 and a fourth pin 16, and a plane including the third and fourth pins 15 and 16 is disposed not to be in parallel with, but to be slightly inclined to a plane including the aforesaid first and second pins 13 and 14.