A therapeutic agent for tumor for combined use of a compound or pharmaceutically acceptable salt thereof represented by Formula (I) and a compound represented by Formula (II): wherein R 1 is C 1-6 alkyl or C 3-8 cycloalkyl, R 2 is a hydrogen atom or C 1-6 alkoxy, and R 3 is a hydrogen atom or a halogen atom, exhibits an excellent antitumor effect compared to cases where these are individually used.