The present invention provides a recombinant strain, construction method thereof and a method for producing acid phosphatase using the recombinant strain. In the invention, the phosphatase gene is obtained from Pseudomonas aeruginosa by a molecular biology method, the constructed expression plasmid is transformed into E. coli BL21 (DE3). The purified enzyme and whole cells were used for the conversion of ascorbic acid to ascorbic acid-2-phosphate. Ascorbic acid-2-phosphate can be efficiently produced by controlling the ratio of substrates. When the conversion reaction is performed at pH 4.5 under 40° C. for 8 h, the output of ascorbic acid-2-phosphate reaches 54.8 g/L, the conversion is 42.9% and the space time yield is 6.9 g/L/h.