We analyzed PILs of placebo-controlled acupuncture trials to see how placebo acupuncture was described to the study participants. Approximately 57% of the studies fully informed the participants of placebo acupuncture while the rest of the studies either gave deceitful or no information on placebo. A half of the studies were evaluated as ideally blinded. When BI values of the included studies were compared between FD and no disclosure (DD/MI) categories, placebo groups in the latter were more likely than those in FD category to make opposite guesses on the intervention, i.e., guessed that they have received real acupuncture. Although this difference did not reach statistical significance, it may reflect more wishful thinking of placebo groups in no disclosure category than those in FD category. Studies with no disclosure reported greater treatment effects for real acupuncture than those with FD, possibly due to enhanced expectations.