Abstract: Objective：To evaluate the efficacy of two kinds of detection systems for determination of lipoprotein (a) ［Lp(a)］ in prediction of acute ischemic cerebral infarction. Method：A retrospective study was conducted on 147 patients with acute ischemic cerebral infarction in Liaocheng People′s Hospital from January to June of 2015, in which two detection system, i.e., 1 (indicated by mg/L) and 2 (indicated by nmol/L), were used to measure the levels of Lp(a) in serum of the patients. The efficiencies in forecasting acute ischemic cerebral infarction of the two detection systems were evaluated through receiver operating characteristic (ROC) curve, and the degrees of neurological deficit were assessed according to US National Institute of Health Stroke Scale (NIHSS score). The relationship between the levels of Lp(a) determined by the two systems and the scores of NIHSS were analyzed. Results：The measured values of the both systems were higher than those of the control group, and the differences were statistically significant (all P<0.01). The sensitivity and specificity of the Detection System 2 in forecasting acute ischemic cerebral infarction were significantly higher than those of Detection System 1. The AUC of Detection System 1 in forecasting acute ischemic cerebral infarction was 0.801 (95%CI: 0.718-0.874), optimal cutoff value was 168.05 mg/L, sensitivity was 71.1%, and specificity was 61.9%, while the AUC of Detection System 2 was 0.919 (95% CI: 0.8770.961), optimal cut off value was 19.95 nmol/L, sensitivity was 78.7%, specificity was 95.2%. The Detection System 2 showed better correlation of Lp(a) levels with the degrees of neurological deficit (r=0.587) than that of Detection System 1 (r=0.462). Conclusion：The predictive value of Detection System 2 for acute ischemic cerebral infarction should be higher than that of Detection System 1