A method in sand/water remediation by using photocatalytic fuel cell is related to the sewage treatment and sand/soil remediation field. The characteristic photocatalytic fuel cell uses photons or solar energy to produce highly active electron/holes is introduced to degrade pollutants. In the constructed visible light photocatalytic fuel cell, there is overlying water above polluted sands in a tubular reactor. Allowing static adsorption equilibrium to buildup, in the built photocatalytic fuel cell, the photocatalytic anode and photoelectric catalytic cathode are connected by wires with an external resistance. Using 50 W halogen lamp as the light source, it maintains photocatalysis and electro-catalytic reactions to degrade pollutants in the method. By degrading the pollutants in the overlying water, the pollutants in the sand are also desorbed and degraded, and rapidly decreased to a very low level. Thus in this method water purification treatment and sand remediation take place simultaneously.