A visualization study on the behavior of bubbles has been carried out for pool boiling of R141b on a horizontal transparent heater at pressure 0.1 MPa．The behaviors of bubbles were recorded by a high-speed camera placed beneath the heater surface．The departure diameter, departure time of bubbles and nucleation site density at different heat flux were obtained．The visualization results show that bubble departure diameter and departure time decrease，while the nucleation site density increases as the heat flux increases．It is also observed that there is no liquid recruited into the microlayer in the experiment．Based on the experimental results，boiling curve for R141b was predicted by using the dynamic microlayer model．As a result，the agreement betwen the predictive result based on the dynamic microlayer model and the experiment data for boiling curve of R141b is good at high heat flux．