Aim To explore the myocardial damage, abnormal electrocardiogram characteristics of patients infected with SARS-CoV-2 Omicron variant in Zhuhai. Methods 84 patients with SARS-CoV-2 Omicron variant (Omicron variant group) admitted to the Fifth Affiliated Hospital of Sun Yat-sen University from January 13 to March 0,2 were included, and 88 patients with non SARS-CoV-2 Omicron variant (non-Omicron variant group) from January 17 to February 7,0 were included. A retrospective study was conducted to compare myocardial damage, abnormal electrocardiogram and clinical characteristics between the two groups. Results The mean age of patients in Omicron variant group was smaller than that in non-Omicron variant group [(36.6±15.6) years vs. (49.8±14.3) years, P＜0.01], and the proportion of patients with body temperature, systolic blood pressure and fever at admission was lower than that of non-Omicron variant group (P＜0.05). The neutrophil/lymphocyte ratio [(2.93 (3.3,5.81) vs. 7.06 (2.2,1.27), P＜0.001], interleukin-2 (IL-2) and interleukin-6 (IL-6) levels in Omicron variant group were significantly lower than those in non-Omicron variant group (P＜0.01). Cardiac troponin I (cTnI) was negative in Omicron variant group, and the concentrations of cTnI, creatine kinase-MB isozyme (CK-MB) and N-terminal pro-brain natriuretic peptide (NT-proBNP) and the proportion of patients with elevated levels were significantly lower than those of non-Omicron variant group (P＜0.01). The incidence of abnormal electrocardiogram in Omicron variant group was also significantly lower than that in non-Omicron variant group (25.0% vs. 42.0%, P＝0.001), sinus tachycardia, atrial premature beats and T wave changes were the main symptoms. Atrial premature beats,Tü wave changes, ST segment depression and bundle branch block were the main symptoms in non-Omicron variant group. Conclusions The patients infected with SARS-CoV-2 Omicron variant in Zhuhai may not have obvious myocardial damage because most of the patients have been vaccinated with COVID-19 vaccine. The incidence of abnormal electrocardiogram is also significantly lower than that of non-Omicron variant group, mainly sinus tachycardia, atrial premature beats and T wave changes.