New campotothecin derivatives and a process for preparing same are disclosed, which are represented by the general formula: ##STR1## wherein R.sup.1 represents a lower alkyl group, R.sup.2 represents a hydrogen atom or an amino, hydroxyl, lower acylamino or lower alkoxy group, R.sup.3 represents a hydrogen or halogen atom or a lower alkyl, hydroxyl, lower alkoxy, nitro, amino, cyano or di(lower alkyl)amino group, R.sup.4 represents a hydrogen or halogen atom or a lower alkyl, hydroxyl, lower alkoxy, lower alkylthio, amino, cyano or di(lower alkyl)amino group, and R.sup.5 represents a hydrogen or halogen atom or a hydroxyl or lower alkoxy group, with the proviso that all of the R.sup.2, R.sup.3, R.sup.4 and R.sup.5 substituents should not be a hydrogen atom and also that if any one of the R.sup.2, R.sup.3, R.sup.4 and R.sup.5 is a hydroxyl or lower alkoxy group, all of the other three substituents should not be a hydrogen atom.