Manufacturing method of steel plate for high-corrosion-resistance photovoltaic support

The invention discloses a manufacturing method of a steel plate for a high-corrosion-resistance photovoltaic support. According to the method, an acid plating continuous process is adopted, and an adopted galvanized substrate comprises the following chemical components in percentage by weight: 0.050%-0.080% of C, 0.10%-0.20% of Si, 0.9%-1.25% of Mn, less than or equal to 0.019% of P, less than or equal to 0.003% of S, 0.020%-0.040% of Als, 0.010%-0.040% of Ti, 0.015%-0.030% of Nb and the balance of Fe and inevitable impurities. The zinc liquid used for galvanizing comprises the following chemical components in percentage by weight: 5-6.5% of Al, 2.5-2.8% of Mg, less than or equal to 0.03% of Fe and the balance of zinc and inevitable impurities. The steel plate produced by the manufacturing method can realize the application replacement of'high-strength thinning 'and'thick zinc layer' of the photovoltaic bracket, and reduces the material consumption and material cost for producing the photovoltaic bracket whil