Aims To use cognitive modelling to investigate psychological processes underlying decision‐making in male abstinent heroin misusers (AHMs). Design A case–control study design. Setting A drug misuse treatment centre in Taiwan. Participants Eighty‐eight male AHMs and 48 male controls. Measurements Four parameters representing the attention to wins, learning rate, response sensitivity and incentive of heroin‐related stimuli from the modified Go/NoGo discrimination task. Findings A modified cue‐dependent learning (CD) model with four parameters representing attention to wins, learning rate, response sensitivity and incentive of heroin‐related stimuli had a lower value of the sum of Bayesian information criterion (showing a better fit) than the original CD model (9555.50 versus 11 192.22, P < 0.001). The AHM group had a higher value of the heroin‐incentive parameter than the control group (0.26 versus −1.66, P < 0.05). The attention to wins and heroin‐incentive parameters were associated positively with total commission rate and negatively with total omission rate in the AHM group (P < 0.001). Conclusions Male abstinent heroin misusers appear to be more influenced by heroin‐related stimuli during decision‐making than males with no history of heroin misuse.