Abstract: Objective To investigate the predictive value of Rho-associated coiled-coil containing kinase1 (ROCK1) and ROCK2 for no reflow in patients with acute ST segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI). Methods A total of 168 STEMI patients who received PCI were selected as study objects, and were divided into no reflow group and normal blood flow group based on whether no reflow occurred, were divided into high expression group and low expression group based on the expression of ROCK1 and ROCK2. Enzyme linked immunosorbent assay was used to detect the levels of serum ROCK1 and ROCK2. The differences in serum levels of ROCK1 and ROCK2 between the no reflow group and the normal blood flow group were analyzed, and the risk factors for no reflow in STEMI patients undergoing PCI treatment were analyzed, the predictive value of ROCK1 and ROCK2 for no reflow in STEMI patients undergoing PCI treatment were analyzed. Results Of 168 STEMI patients, no reflow occurred in 46 cases (27.38%). The Killip grade, time from onset to hospital admission, proportion of patients who did not use prophylactic no reflow, serum ROCK1 level and serum ROCK2 level in the no reflow group were higher or longer than those in the normal blood flow group (P<0.05). The incidence of no reflow in ROCK1 high expression group was higher than that in ROCK1 low expression group, and the incidence of no reflow in ROCK2 high expression group was higher than that in ROCK2 low expression group, the differences were statistically significant (P<0.05). The incidence rates of no reflow in the ROCK1 high expression group and ROCK2 high expression group were higher than that in the ROCK1 low expression group and ROCK2 low expression group (P<0.05). Multiple Logistic regression analysis showed that Killip grade of III to IV, longer onset to admission time, no using prophylactic no reflow drugs, and higher serum levels of ROCK1 and ROCK2 were all risk factors for no reflow in STEMI patients undergoing PCI (P<0.05). Receiver operating characteristic curve showed that ROCK1 and ROCK2 had high predictive value for PCI in STEMI patients without reflow, and the predictive value was increased after the combination of ROCK1 and ROCK2. The area under the curve was 0.789(95%CI, 0.711 to 0.867). Conclusion High serum levels of ROCK1 and ROCK2 are both risk factors for no reflow in STEMI patients undergoing PCI, and their combination has high predictive value for no reflow.