Based on the imaging plate (IP) techniques and taken the overlapping as well as fading effects into account, a new track counting method for alpha particles was developed and testified in this study. A photostimulated luminescence (PSL) value of 0.25 was supposed as a reasonable threshold for discriminating alpha particles from beta and natural background radiation. Compared with the previous method (PSL value method), it was found that the new method had a better linearity and a lower detection limit for measurements of alpha radiation, and the fading effect on the discrimination was also smaller. (C) 2011 Elsevier Ltd. All rights reserved.