To determine the effects of 80-mg atorvastatin administration for the first time in patients with acute ST segment elevation myocardial infarction (STEMI) before emergency percutaneous coronary intervention (PCI). A total of 118 patients with STEMI who underwent emergency PCI were enrolled in this study. The patients were divided into 80-mg group (n = 59) and 40-mg group (n = 59), according to the loading dose of atorvastatin firstly before operation. The occurrence of no-reflows and changes of HbA1c were observed preoperatively and postoperatively on second and fifth days. All patients were followed up for 1 year with major adverse cardiac events (MACE) recorded. The incidence of no-reflow in 80-mg group was obviously lower than in 40-mg group (13.56% vs. 25.42%) (χ = 4.374, P = 4.374). The preoperative HbA1c levels exhibited no significant difference between 80-mg group and 40-mg group (P > 0.05). The postoperative HbA1c levels in 2 groups showed a trend of gradual decline, which were lower in 80-mg group than in 40-mg group for second day, fifth day, first month, sixth month, and 12th month (all P < 0.05). The postoperative incidence of MACE in 80-mg group was significantly lower than in 40-mg group for sixth and 12th months (both P < 0.05). The incidence of MACE in patients with reflow in 80-mg and 40-mg groups was significantly higher than in patients with no-reflow who were in 80-mg and 40-mg groups for postoperative 12th month (both P < 0.05). The first loading high dose of atorvastatin can significantly prevent occurrence of postoperative no-reflow in patients with STEMI after PCI, reduce HbA1c levels and the incidence of MACE. Clinical randomized controlled trial with larger sample size is required to confirm this finding.