Abstract: A tricyclic pyrrole or pyrazole derivative represented by the following general formula (I), or a pharmaceutically acceptable salt thereof, which shows strong affinity and selectivity for the 5-HT2C receptor and is useful for the treatment of central nervous system diseases such as sexual disorders, eating disorders, anxiety, depression and sleeping disorders. (In the above formula, each symbol means as follows; Y ring: an unsaturated five-membered ring which may have 1 to 3 of one or more types of hetero atom(s) each selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom or an unsaturated six-membered ring having 1 or 2 nitrogen atom(s), X: a bond or a carbon atom, a double bond or a single bond, V: a nitrogen atom or a group represented by a formula CH, and A: a straight or branched lower alkylene group which may be substituted with a halogen atom or a cycloalkyl group).