The invention discloses an in-situ mineralization and dyeing method for high color fastness dyed product of natural protein fiber, comprising the steps of adding a textile product to be dyed into dyeing equipment, adding soft water for the first time, and keeping a dyeing bath circulation; carrying out dyeing processing, with dyeing residual liquid not discharged temporarily after dyeing is finished; cooling the dyeing residual liquid, adding an aid XFL, holding the temperature for circulation, and discharging a first residual liquid; adding soft water for the second time, heating for circulation, and discharging a second residual liquid; adding soft water for the third time, adding aids XBM and XYM in sequence, uniformly circulating, heating, holding the temperature, and discharging a third residual liquid; adding soft water for the fourth time, heating for circulation, and discharging a fourth residual liquid. According to the in-situ mineralization and dyeing method, the implementation of in-situ mineralization allows water to be saved by 50% on the premise of ensuring relevant color fastness indexes of dyed products, the dyeing process is obviously shortened, the production efficiency is improved, and meanwhile, the energy-saving effect is achieved.