This study examined the effects of dry needling on chronic heel pain due to plantar fasciitis. During this single-blinded clinical trial, 20 eligible patients were randomized into two groups: A case group treated with dry needling and a control group. Patients’ plantar pain severity, (using modified visualanalog scale [VAS] scoring system), range of motion of ankle joint in dorsiflexion [ROMDF] and plantar extension [ROMPE] and foot function index (using standard questionnaires of SEM5 and MDC7) were assessed atbaseline, four weeks after intervention and four weeks after withdrawing treatment. Independent sample t-test,Mann-Whitney U test, paired t-test, Wilcoxon signed rank tests, and chi square test were used for data analysis. The mean VAS scores in the case group was significantly lower than the control group after fourweeks of intervention (p<0.001). Comparison of the ROMDF and ROMPE did not reveal any significant changesafter four weeks of intervention in the case and control groups (p=0.7 and p=0.65, respectively). The mean ofMDC7 and SEM5 scores in the case group were significantly lowerthan the control group following four weeksof intervention (p<0.001). Despite the insignificant effect on ROMDF and ROMPE, trigger point dry needling, by improvingthe severity of heel pain, can be used as a good alternative option before proceeding to more invasive therapies of plantar fasciitis.