OBJECTIVE： To investigate the significance of pentraxins 3 （PTX-3） in diagnosis and treatment of acute coronary syndromes （ACS） combined with depression. METHODS： The inpatients with ACS， depression or ACS combined with depression were selected from our hospital during Dec. 2015-Mar. 2018， and then divided into ACS group （84 cases）， depression group （85 cases）， ACS combined with depression group [by chemical drug treatment （40 cases） and by Chinese patent medicine treatment （40 cases）]. Healthy volunteers at the same period in our hospital were regarded as control group （90 cases）. ACS groups was given Aspirin enteric-coated tablets （50-150 mg every time， qd）+Tongxinluo capsules （2-4 capsules every time， tid）. Depression group was given Sertraline hydrochloride tablets （50 mg every time， qd）+Xiaoyao pills （9 g every time， bid）. ACS combined with depression group was given chemical drugs （Aspirin enteric-coated tablets+Sertraline hydrochloride tablets， same usage and dosage as above） and Chinese patent medicine （Tongxinluo capsules+Xiaoyao pills， same usage and dosage as above）， for consecutive 4 weeks. The contents of PTX-3 and its mRNA expression in plasma were analyzed retrospectively before and after treatment. Therapeutic efficacies and the occurrence of ADR were compared in each group. RESULTS： Before treatment， the plasma contents of PTX-3 and its mRNA expression in ACS group， depression group， ACS combined with depression group were significantly higher than control group， and ACS combined with depression group was significantly higher than ACS group and depression group （P＜0.01）. After treatment， above indexes of ACS group， depression group， ACS combined with depression by chemical drug treatment group and by Chinese patent medicine treatment group were all decreased significantly， compared with before treatment； and the difference of above indexes before and after treatment of ACS combined with depression by chemical drug treatment group were significantly higher than other groups （P＜0.01）. Total response rates of cardiovascular symptoms were 80.9％， 77.5％， 72.5％ in ACS group， ACS combined with depression by chemical drug treatment group and by Chinese patent medicine treatment group； total response rates of depression symptoms were 84.7％， 82.5％， 77.5％ in depression group， ACS combined with depression by chemical drug treatment group and by Chinese patent medicine treatment group， without statistical significance （P＞0.05）. Except for 3 patients with mild gastrointestinal discomfort， no obvious ADR was observed in other patients. CONCLUSIONS： The expression of PTX-3 in patients with ACS， depression， ACS combined with depression are higher than healthy volunteers. Drug treatment can significantly decrease the expression of PTX-3 in above patients； moreover， chemical drug may has more advantages in short period. PTX-3 can be regarded as a diagnosis and treatment biomarker of ACS combined with depression patients.