The paper describes a study of canal and supplemental ground water used by 544 farmers for wheat crop in the Rechna Doab catchment of Pakistan. The main objective was to assess the on-farm financial gains through conjunctive water use. For econometric analysis, a linear relationship between the wheat production and different determinant variables was assumed. The results highlighted the problem of increased use of tubewells water in the saline zones that had resulted in the deterioration of the groundwater quality and led to the problem of permanent upconing of saline groundwater. Conjunctive water management increased the farm income by about Rs. 1000 and 5000 per hectare compared to only using the canal and tubewell water, respectively The results of financial analysis show that the net-gains were 30 percent higher on the farms using conjunctive water management as compared to the farms using only tubewell irrigation.