Objective To explore clinical significance of changes of serum levels of Interleukin-18 (IL-18) and plasma lysophosphatidic acid (LpA) before and after treatment in patients with acute cerebral infarction. Methods The levels of IL-18, LpA and D-dimer (D-D) in 38 cases of acute cerebral infarction before and after treatment, and 35 healthy controls were detected by using ELISA, biochemistry. Results The average levels of IL-18, LpA and D-D in patients with acute cerebral infarction before treatment were significantly higher than those in controls (P＜0.01). There were no significant difference on the average levels of IL-18, LpA and D-D between patients after 2 weeks treatment and controls (P＞0.05). Conclusion The detection of changes of serum IL-18, plasma LpA and D-D Levels before and after treatment in patients with acute cerebral infarction might be helpful to monitor the theraputic efficacy and prognosis.