The aim of the study was to determine the effectiveness of Attentional Bias Modification (ABM) and Cognitive Behavioral Therapy (CBT) on the reduction of pain intensityin patients with chronic pain. This study was a quasiexperimental pretest-posttest design with control group. All patients who referred to physiotherapy clinics for pain during 2015 were participated in the study. They completed the Brief Pain Inventory-short form (BPI-SF) for assessing severity of pain. Attentional bias was evaluated using computerized Dot-Probe task. The patients with chronic pain were screened by diagnostic criteria of DSM-V; neurologic diagnosis, and interview. 36 people were selected and randomly divided to three groups computer-based ABM, CBT, and control (12 cases in each group). Group A was trained in 8 sessions-each 15 minutes with the modified computerized Dot-Probe task for attentional bias modification. Group B was trained in 11 sessions-each 45 minutes with CBT program of Turk and Ferry for the chronic pain treatment. And Placebo program was administered for group C in which they completed 8 classic Dot- Probe sessions. In the end, for the posttest (T2) the participants were tested to identify the changes in biased attention to the emotional stimuli using classing Dot-Probe tasks, and BPI questionnaire to evaluate the changes of severity of pain. Data were analyzed using one-way variance analysis(ANOVA). On the BPI-SF, CBT more reduced the pain intensitythan computer-based ABM.In addition ABM treatment is more effective in reduction of attentional bias.Both of treatments are effective but CBT is more effective than ABM in reduction of pain intensity.