The invention provides a technical method for controlling and raising the PH value of galvanizing solution on a fingerprint resistant continuous and automatic production line of the electro-galvanizing and roller coating of a rolled plate; the galvanizing solution rich in zinc ions enters a galvanizing bath from a dezincification bath; the technique is characterized in that: after entering the galvanizing bath from the dezincification bath, the galvanizing solution enters a circulating tank after going through an on-line filtering machine and then enters the galvanizing bath from the circulating tank; the galvanizing solution in the galvanizing bath returns to the galvanizing bath through the circulating tank; and the galvanizing solution is electrolyzed by the current density of 0.1A/dm<2> to 0.3A/dm<2> in an electrobath. The electrobath is internally provided with three anodes and two cathodes at intervals. The technical proposal has the advantages of not only removing hazardous metal impurities, but also increasing dezincification speed, particularly properly raising the PH value, increasing the overpotential of hydrogen, reducing hydrogen evolution, fining electro-galvanizing layers and reducing electric energy consumption, thereby greatly improving product quality.