To provide a gear transmission provided with a rotation resistance adding mechanism, in which generation of idling rattle noise can be securely prevented in all the driving ranges even where fluctuation width of the rotation resistance inputted to an input shaft due to fluctuation of oil temperature or the like is relatively large.

This gear transmission is provided with an input shaft 12 provided with a top gear 33 to which power from an engine 1 is inputted through a clutch 7, a counter shaft 32 provided with a counter shaft drive gear 36 to be engaged with the top gear 33, and stored in a transmission 8 with relation to the input shaft 12, a rotation resistance adding means 38 to add rotation resistance to the counter shaft 32, an oil temperature detecting means 52 to detect oil temperature Tm of oil in the transmission 8, an engine rotation detecting means 53 to detect engine rotation Ne, and a control means 46 to drive the rotation resistance adding means 38 to add rotation resistance to the counter shaft 32 when the engine 1 is in an idle rotation range Nea, as the oil temperature Tm is in a prescribed temperature range Tm1.