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We study a role of the proto-accretion disk during the formation of the planetary sys-tem, whichis motivatedwith recentX-rayobservations. Thereis anobservationalcor-relation of the mass of extrasolar planets with their orbital period, which also showsfect alone. Besides, most of planetary formation theories predict the lower limit ofsemimajor axes of the planetary orbits around 0.01 AU. While the migration theoryinvolving the accretion disk is the most favorable theory, it causes too fast migrationand requires the braking mechanism to halt the planet. . . .. AU. The induced gap into stop the planet. We xplore the planetary evaporation in the accretion disk as an-other possible scenario to explain the observational lack of massive close-in planets.We calculate the location where the planet is evaporated when the mass and the ra-dius of the planet are given, and nd that the evaporation location is approximatelyproportional to the mass of the planet as.. . . .. and the radius of the planet as.. . .. .Therefore,we concludethat eventhe standardcool accretiondisk becomesmarginallyhot tomakethesmall planetevaporateat. 0.01AU. We discuss otherauxiliarymech-friction, which may consequently make a larger planet evaporate.