An real time and in situ fixing method by heating with a CO 2 laser beam is suggested to thermally fix a small local hologram in a bulk of Fe:LiNbO 3 photorefractive crystal. To form a heating up to 100￣200℃ volume with the shape similar to the heat transfer equations, different heating modes with or without metal absorbers for heat guiding by using a continuos or pulsed laser beam are analyzed. The optimal mode may be the case of pulsed heating with absorbers. On this basis, experiments are designed and demonstrated. It is shown that the fixing process by CO 2 laser beam is very short compared with the process by oven, and the fixing efficiency is high.