A self-compensating hydrostatic journal bearing is disclosed, which is substantially a base provided for a spindle to mounted thereat passing through a hole thereof, while allowing a gap to be formed between the circumference surface of the hole and the spindle for a hydraulic fluid to flow therethrough. There are at least two oil holes formed on the base, and correspondingly, there are at least two first chambers formed on the circumference surface for allowing each first chamber to be in fluid communication with one of the at least two oil holes, and for each first chamber, there is one second chamber being arranged in the vicinity thereof. When the spindle is forced to bias, the gap axially opposite to the bias is changed for causing the hydraulic fluid to flow inside the channels between the first chambers and the second chambers correspondingly and thus accomplishing a fluid self-compensating process.