The present invention relates to an antidepressant containing as an active ingredient a triazine derivative or a pharmaceutically acceptable salt thereof, the derivative being represented by the following Formula (I): ##STR1## in which, R.sup.1 represents hydrogen, substituted or unsubstituted lower alkyl, or substituted or unsubstituted lower alkanoyl; R.sup.2 represents hydrogen, substituted or unsubstituted lower alkyl, substituted or unsubstituted lower alkenyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted aralkyl, or a substituted or unsubstituted heterocyclic group; R.sup.3 represents a substituted or unsubstituted heterocyclic group; X represents a single bond, O, S, S(O), S(O).sub.2, or NR.sup.4 (in which R.sup.4 represents hydrogen, or substituted or unsubstituted lower alkyl; or R.sup.2 and NR.sup.4 are combined to form a substituted or unsubstituted 4 to 6-membered saturated heterocyclic group); and A represents N or CR.sup.5 (in which R.sup.5 represents hydrogen, or substituted or unsubstituted lower alkyl).