A slide rail assembly includes a first rail, a second rail, a first locking mechanism, and a second locking mechanism. The second rail can be displaced with respect to the first rail. The first locking mechanism and the second locking mechanism are disposed at two different portions of the second rail respectively and can be locked to the first rail separately in order to keep the second rail at either of two predetermined extended positions. The first locking mechanism and the second locking mechanism can then be operated and thereby unlocked from the first rail so that the second rail can be retracted with respect to the first rail.