The electrodeposition of Pt film is carried out in an electrolytic bath of different pH (pH varied from 2 to 4) at constant potential -0.35V for 30 min. The prepared Pt film is studied by different analyzing techniques as well as used as a cathode electrode in photovoltaic (PV) cell assisted water electrolysis system for hydrogen production. The film properties show strong dependence on pH of electrolytic solution. Pure Pt film with low mass loading (2.44 x 10(-5) g cm(-2)) is obtained at pH 2, which subsequently undergo oxidation and mass loading also increases with pH. The earth worm like surface morphology is observed in a film deposited at pH 2, which is changed into thorny ball like morphology with pH. The active surface area and the activity for hydrogen evolution show linear relation and decreases with pH. Thus, the highly active Pt film for hydrogen production is obtained at pH 2, which shows about 25% higher hydrogen production and 3500 times lower Pt loading (from 0.07 g cm(-2) to 2.44 x 10(-5) g cm(-2)) than those of commercial Pt mesh. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3582766] All rights reserved.