CONTEXT: The COVID-19 pandemic contributed to a significant rise in mental health issues, including a 70 % increase in Japan's suicide rate. Prior studies suggest that Thought Field Therapy (TFT) can rapidly alleviate psychological distress. OBJECTIVE: To evaluate the efficacy of online TFT as a quick intervention for psychological problems. DESIGN: This study employed the Brief Job Stress Questionnaire, administered to TFT and waitlist (WL) groups before and after the intervention, with the WL group also assessed two weeks prior to the TFT intervention. Follow-up questionnaires were completed by all participants after two additional weeks. SETTING: Subjective Unit of Distress Scale (SUDS) scores for targeted psychological issues were collected across participant groups. PARTICIPANTS: Ninety-nine participants were randomly assigned to either the TFT intervention group or the WL group. INTERVENTIONS: Among the 88 participants who completed the TFT intervention, significant reductions were observed in all negative emotions, including stress-induced mental and physical reactions, irritability, fatigue, anxiety, depression, and somatic complaints (p <
.01). MAIN OUTCOME MEASURES: SUDS scores for 248 issues, including trauma and anxiety, showed a significant decrease from an average of 7 to 1.5 following the TFT intervention (p <
.01) with a large effect size (dz = 2.15). RESULTS: A brief online TFT intervention during the COVID-19 pandemic significantly reduced psychological stress, with sustained effects observed over two to six weeks. This suggests that TFT is an effective accessible tool for mental health and self-care in the absence of face-to-face therapy.