Thirty-two psychotropic substances were listed as designated substances (Shitei-Yakubutsu, 31 compounds and 1 plant) in Japan by the Pharmaceutical Affairs Law in April 2007 for preventing the abuse of these substances. Subsequently, other psychoactive compounds were also added to this category, 40 substances (classified as 12 tryptamines, 17 phenethylamines, 3 piperazines, 6 alkyl nitrites, 1 diterpene and 1 plant) are controlled as designated substances as of July 2009. However, new designer drugs are still distributed in illegal drug market according to the results of our annual survey. This study presents the analysis of four newly distributed designer drugs detected from two products, which were purchased from October 2008 to February 2009 in Japan. As the results of NMR, GC-MS and LC-MS analyses, three phenethylamine derivertives, 1-(2-fluorophenyl)-N-methylpropan-2-amine (N-Me-2-FMP), 1-(2,5-dimethoxy-4-isopropylsulfanylphenyl)propan-2-amine (ALEPH-4) and 1-(2,5-dimethoxy-4-nitrophenyl)propan-2-amine (DON) and a tryptamine derivative, N-ethyl-5-methoxy-N-propyltryptamine (5-MeO-EPT), were detected. N-Me-2-FMP and 5-MeO-EPT were newly identified in this study. Additionally, ALEPH-4 and DON were found as novel illegal drugs distributed in Japan.