This is the first study that focuses on the effects of intradermal acupuncture on insomnia after stroke. We enrolled hospitalized stroke patients with insomnia and assigned them into a real intradermal acupuncture group (RA group) or a sham acupuncture group (SA group) by randomization. The RA group received intradermal acupuncture on shen-men (He-7) and nei-kuan (EH-6) for 2 days, and the SA group received sham acupuncture on the same points. The effectiveness was measured by the Morning Questionnaire (MQ), Insomnia Severity Index (ISI), and Athens Insomnia Scale (AIS). These scales were examined by an independent, blinded neurologist before, and 1 and 2 days after treatment, repeatedly. Thirty subjects (15 in the RA group and 15 in the SA group) were included in the final analysis. The RA group showed more improvement on insomnia than the SA group. Repeated measures analysis detected that there were significant between-subjects effects in the MQ, the ISI and the AIS. In conclusion, we suggest that intradermal acupuncture on shen-men and nei-kuan is a useful treatment for post stroke-onset insomnia.