The utility model discloses a cold water quality stabilizing device in a power generator. The cold water quality stabilizing device comprises a hydrogen ion (H) bed chamber, a hydroxyl ion (OH)bed chamber, a sodium ion/ hydroxyl ion (Na/OH) bed chamber inlet flowmeter, a total flowmeter, a resin trapper, a dosing pump and a dosing box, wherein the H bed chamber is connected in series with the OH bed chamber in the vertical direction; the H bed chamber and the OH bed chamber are connected in series with each other in the vertical direction and then are connected in parallel with the NA/OH bed chamber; the OH bed chamber and the Na/OH bed chamber are respectively connected in series with the resin trapper; the dosing box is filled with a NaOH solution; and the dosing box is connected with the pipeline between the total flowmeter and the resin trapper through the dosing pump. The cold water quality stabilizing device has the advantages that the quality of the water treated by the cold water quality stabilizing device can reach a high industry standard; moreover, the life cycle of ion exchange resin is long; the regeneration of the ion exchange resin after failure is simple; and the cold water quality stabilizing device is convenient to reuse, economical and environment-friendly.