BACKGROUND Acupuncture may improve gastrointestinal symptoms in patients with various disorders, but its efficacy in diabetic gastroparesis is unclear. OBJECTIVE To evaluate the short-term effects of acupuncture on gastric emptying and gastroparesis symptoms in patients with diabetic gastroparesis. METHODS In a single-blind controlled crossover trial, 25 patients with diabetic gastroparesis were randomly assigned to undergo 1 week of real acupuncture (RA) treatment followed by 1 week of sham acupuncture (SA) treatment, or vice versa, with a washout of 1 month in between. Before and after each intervention, gastric retention, the Gastroparesis Cardinal Symptom Index (GCSI), fasting blood glucose (FBG) and HbA1c levels were measured. RESULTS 21 patients completed the study. Compared with SA treatment, RA treatment was associated with significantly greater reductions in gastric retention at 2 h (-11.1±7.0%; 95% CI -13.6% to -6.2%; p<0.01) and at 4 h (-5.0±2.8%; 95% CI -6.0% to -0.2%; p=0.04) and in GCSI score (-8.0±3.4; 95% CI -8.4 to -2.8; p<0.01). There were no significant differences in FBG and HbA1c levels between RA and SA treatments. CONCLUSIONS In patients with diabetic gastroparesis, 1 week of short-term manual acupuncture reduces gastric retention and improves gastroparesis symptoms.