Provided is a mounting table structure for use in forming a thin film on a surface of a target object mounted on the mounting table structure by using a raw material gas including an organic metal compound in a processing chamber. The mounting table structure includes: a mounting table main body which mounts thereon the target object and has therein a heater; and a base which supports the mounting table main body while surrounding a side surface and a bottom surface of the mounting table main body, the base having therein a coolant path where a coolant flows therethrough and being maintained at a temperature higher than the solidification temperature or the liquefaction temperature of the raw material gas, but lower than the decomposition temperature of the raw material gas.