Abstract: In 2018, FDA approved 59 kinds of new drugs in all, breaking the record of 53 set in 1993. There were 34 types of small molecule drugs, which accounted for 64% of the whole new drugs. Of these 34 new small molecule drugs, 9 first-in-class ones marked a milestone for the subsequent drug discovery and development. These include Glasdegib, the world's first small molecule inhibitor targeting Smo through Hedgehog signaling pathway; Ivosidenib, the first small molecule inhibitor targeting mutant IDH1; Tecovirimat, the first small molecule drug for anti-variola virus therapy through targeting p37; Baloxavir marboxil, the first anti-flu drug targeting cap-dependent endonuclease; Elagolix sodium, the first small molecule inhibitor in treating endometriosis by targeting GnRH-R, etc. The research and development of first-in-class drugs is always full of obstacles and challenges. However, once they were successfully recognized as the "heavy bomb" drugs, they would become huge benefits. This article chose the representative first-in-class small molecule drugs that were approved in 2018 as examples to analyze their development processes in an attempt to provide guidance for the research and development of more first-in-class drugs.