The objective of this study was to evaluate olfactory perception in Multiple Chemical Sensitivity (MCS) patients. MCS patients and healthy subjects performed odor threshold test using five odors (β-phenyl ethyl alcohol [A], methyl cyclopentenolone [B], isovaleric acid [C], γ-undecalactone [D], and skatole [E]) of T&T olfactometer, odor identification test using four odors (Japanese orange, Japanese cypress, perfume, and odorless) selected from Odor Stick Identification Test for Japanese (OSIT-J). Psychological evaluation of perceived intensity and pleasantness for each odor used in the threshold and identification tests were also performed. Our results indicated that MCS patients had significantly lower detection threshold for odor D and means of detection and cognition thresholds of five odors, but identification ability was equivalent between MCS patients and healthy subjects. Additionally, perceived intensity and unpleasantness of some odors were significantly higher for MCS patients than for healthy subjects. Because this study was conducted with a small number of volunteers using a limited type of odors, we should increase the reliability of data to investigate the olfactory perception of MCS patients.