A photoelectrochemical cell with a coupled SnO2CdSe nanocrystalline semiconductor electrode has been prepared by sequential deposition of SnO2 and CdSe films onto an optically transparent electrode (OTE), and its photoelectrochemical behavior has been studied. The results show that the coupling of CdSe with SnO2 leads to an improvement in the performance of OTESnO2CdSe over OTECdSe cells in terms of increased incident photon-to-current conversion efficiency, increased stability and smaller reversal of current. The favorable positioning of the energy bands of Sn(O)2 and CdSe is responsible for the above observations. Various photoelectrochemical parameters of the OTESnO2CdSe cell obtained for an incident light power of 0.31mW cm(-2) at 470nm, are as follows : I-sc approximate to 25-30 mu A cm(-2), V-oc approximate to 0.5-0.6 V, ff = 0.47 and a power conversion efficiency of about 2.25%.