Objective To compare the different effects of glucose solution and glucose-insulin-potassium (GIK) solutions on myocardial injury after percutaneous coronary intervention (PCI). Methods A total of 100 patients with identified coronary heart disease undergoing PCI in our hospital from October to November 2012 were prospectively enrolled in this study. They were randomly divided into two matched groups, with 50 in each group. They were all given conventional treatment as guideline recommended. Patients in control group received intravenous injection of 500ml 10% glucose solution at 2 to 4h before PCI, while those in experimental group had GIK solutions (containing 500ml 10% glucose, 10ml 10% potassium chloride and 12 U insulin) instead of glucose solution. Serum contents of creatine phosphokinase isoenzyme MB (CK-MB) and cardiac troponin I (cTnI) were measured before and one day after PCI. Results There was no significant difference in all baseline clinical data between the two groups. The experimental group had very significant higher blood glucose than control [(11.9±3.6) vs (5.3±3.7)mmol/L, P＜0.001] before PCI, and the value was also higher after PCI [(8.8±4.2) vs (5.1±3.9)mmol/L, P＜0.001]. There was no case from the experimental group with blood glucose ≤5.0mmol/L, but there were 7 (14.0%) found in control group. Both groups had obvious increased CK-MB and cTnI levels after PCI, but control group had more significant increases, with patients had more increased CK-MB by 1- to 3-folds and cTnI by over 3-folds (both P＜0.05). Conclusion Glucose solution applied preoperatively protect patients more significantly against myocardial injury when compared with GIK solutions.