Objective. To explore the efficacy of Herb-partitioned moxibustion in treating IBS-D patients. Method. 210 IBS-D patients were randomly assigned on a 3 : 3 : 2 basis to group HM, group FM, or group PB for 4-week treatment. The change of GSRS total score at weeks 4 and 8, the changes of GSRS specific scores, and adverse events were evaluated. Results. Patients in group HM and group FM had lower GSRS total score at week 4 (1.98 ± 0.303, 2.93 ± 0.302 versus 3.73 ± 0.449) and at week 8 (2.75 ± 0.306, 3.56 ± 0.329 versus 4.39 ± 2.48) as compared with patients' score in group PB. However, there was no significant difference of GSRS total score between group HM and group FM. The effect of HM was significantly greater than that of orally taking PB in ameliorating the symptoms of rugitus (0.38 versus 0.59, P < 0.05), abdominal pain (0.28 versus 0.57, P < 0.01), abdominal distension (0.4 versus 0.7, P < 0.01), and increased passage of stools (0.06 versus 0.25, P < 0.01) at the end of treatment period. In the follow-up period, patients' therapeutic effect in group HM remained greater than that in group FM (in abdominal pain, abdominal distension, and increased passage of stools) and that in group PB (in loose stools). Conclusions. HM appears to be a promising, efficacious, and well-tolerated treatment for patients with IBS-D.