Objective To explore the effects of the transtheoretical model(TTM)-based intervention in patients undergoing coronary angiography(CAG).Methods Totally 146 patients who were scheduled to undergo CAG at Fuwai Central China Cardiovascular Hospital from May 2021 to May 2022 were selected by convenience sampling.Patients admitted from May to November 2021 were assigned to the control group(n=73),and those admitted from December 2021 to May 2022 were assigned to the observation group(n=73).The control group received routine care,while the observation group received TTM-based intervention.The effects of the intervention were evaluated using the Self-Rating Anxiety Scale(SAS),the Self-Rating Depression Scale(SDS),and a self-designed CAG compliance assessment form.Results After the intervention,SAS and SDS scores decreased in both groups,with the observation group scoring significantly lower than the control group(P<0.05).The CAG compliance in the observation group was also significantly higher than that in the control group(P<0.05).Conclusions The TTM-based intervention can improve the psychological state of CAG patients and enhance their compliance with CAG procedures.