The therapeutic approach to myofascial TMD should focus on pain relief and rehabilitation of function. This study investigated whether pressure release technique (PRT) is effective for reducing pain in people with chronic myofascial temporomandibular disorders (TMD). A single-blinded randomised parallel-group trial, with 3 months follow-up was conducted. A total of 72 patients were randomly allocated to receive PRT or sham PRT. Primary outcome was pain assessed with a visual analogue scale (VAS). Secondary outcomes included pressure pain thresholds (PPTs), range of opening of the mouth (ROM), Neck Disability Index (NDI), Pain Catastrophizing Scale (PCS), Tampa Scale for Kinesiophobia (TSK-11), State-Trait Anxiety Index (STAI) and State-Trait Depression Index (ST-DEP). All parameters were assessed at baseline, at the end of the treatment and at 3 months follow-up. Statistical analysis was performed by ANOVA. There were significant main effects of time, group and interaction between time and group (F ≥ 21.92; p < .001) on VAS pain. Post hoc tests showed a significant reduction in VAS pain scores in the PRT group (≥31.9%; p < .001). Effect sizes were moderate in the PRT group at all follow-up periods (≥1.25 Cohen's d). Also, there were significant effects of time in secondary outcomes (F ≥ 9.65; p < .001), and there were also interactions between time and group (F ≥ 3.82; p < .002) with better effects in the PRT group. The inclusion of PRT to conventional management with occlusal splints and self-care management appears to be effective to improve self-reported levels of pain in patients with chronic myofascial TMD pain. Retrospectively registered (ClinicalTrials.gov: NCT03619889).