Purpose: Although cardiac toxicity is a key parameter of significant toxicity, in antidepressant intoxication, there are few studies on the cardiac toxicity of serotonin reuptake inhibitor and the intoxication with the new generation of antidepressants. The aim of this study is to investigate the relative cardiac toxicity of serotonin reuptake inhibitor and intoxication with the new generation of antidepressants as compared with that of tricyclic antidepressant intoxication. Methods: We retrospectively reviewed the medical records of 109 antidepressant intoxicated patients who visited the Emergency Department from January, 2005 to December, 2009 to collect and analyze the demographic and clinical data. Sixteen patients were excluded. The enrolled seventy eight patients were classified into three groups: the tricyclic antidepressant group (TCA) (n=32), the selective serotonin reuptake inhibitor subgroup (SSRI) (n=28) and the new generation antidepressant subgroup (NGA) (n=18). Results: The demographic and clinical data of the SSRI and NGA groups were not significantly different from that of the TCA group. The QRS duration of the SSRI subgroup ($86.4{pm}12.0$ msec) and the NGA subgroup ($91.8{pm}11.9$ msec) was not significantly different from that of the TCA group ($90.0{pm}13.5msec$) (p=0.598). The QTc interval of the SSRI group ($444.5{pm}33.5msec$) and the NGA group ($434.9{pm}35.9msec$) (p=0.260) were not significantly different from that of the TCA group ($431.2{pm}44.1msec$) (p=0.287). Conclusion: Intoxication with SSRI and the new generation antidepressants seemed to show significant cardiac toxicity, like what is seen in tricyclic antidepressant intoxication. Clinicians must pay attention to SSRI and new generation antidepressant intoxication.