Aim To explore the relationship between lipoprotein-associated phospholipase A2 (Lp-PLA2) levels and carotid atherosclerotic plaque in patients with acute cerebral infarction (ACI). Methods A total of 82 ACI patients from June 2013 to October 2014 in our hospital were selected as cerebral infarction group, and a total of 82 healthy people were selected as control group. The total carotid atherosclerotic plaque score were tested by color Doppler ultrasound. The serum Lp-PLA2 levels were detected by ELISA. The relationship between serum Lp-PLA2 levels and acute cerebral infarction size, carotid atherosclerotic plaque Crouse score in patients were analyzed by Spearman correlation. Results The Lp-PLA2, hs-CRP, TG, TC and LDLC levels in infarction patients were significantly higher than those in control group, HDLC levels were significantly lower than that in control group (P＜0.05). Crouse score, Lp-PLA2 levels had significant differences among the three groups of carotid atherosclerotic plaque block grade Ⅰ, Ⅱ, Ⅲ. Lp-PLA2 levels increased with the grade and the degree of injury (P＜0.05). Lp-PLA2 levels was positively correlated to Crouse score, infarct size (r＝0.823 and r＝0.879, all P＜0.05). Conclusion It shows that Lp-PLA2 levels and atherosclerotic cerebral infarction are closely related, Lp-PLA2 levels may reflect carotid atherosclerotic plaque and infarct size, which can be used as predictors of cerebral infarction.