Aim The role of clopidogrel in treating patients with acute ischaemic stroke is unclear. We have conducted the clinical trial in order to evaluate the efficacy and safety of clopidogrel with a loading dose in treating patients with non-cardiogenic acute ischaemic stroke. Method Clopidogrel loading dose versus maintenance dose to treat patients with acute ischaemic stroke in China (CLASS-China) was a prospective, randomised, double-blind and placebo-controlled clinical trial in China. Patients with acute ischaemic stroke of non-cardiogenic origin within 48 hours of onset were enrolled and those received thrombolysis were excluded. Enrolled patients were divided into two treatment groups: loading dose and routine dose. The primary outcome was the incidence of stroke recurrence or progression within 7 days. Primary safety outcome was measured by life-threatening haemorrhage. An intent-to-treat analysis was used for the statistical analysis. Results From March 2008 to March 2010, a total of 303 patients from 16 centres were recruited into this study; six were excluded because of lack of basic information. Since the enrolment was slow and the study drug expired in March 2010, this clinical trial was stopped earlier than planned. No significant baseline and demographic differences were seen between the two groups. There was no difference in primary outcome between the loading dosage group 16.1% (24/149) and control group 14.9% (22/148), respectively (p=0.782). The mortality and disability rate within 90 days in loading dose group (19.6%) was slightly lower than that in controlled group (23.4%), p=0.444. Loading dose group had two (1.3%) cases of fatal haemorrhage and control group had four (2.7%) within 90 days, p=0.674. No significant difference was detected in other adverse events between the groups. Conclusion In our study stopped early due to slow enrolment, loading dose of clopidogrel does not reduce the risk of recurrent stroke. Future trials with sufficient number of patients enrolled are needed to re-examine this hypothesis.