The economically optimum yield for INIA 66 wheat was obtained by using 150 lbs of nitrogen and 30 lbs of phosphorus per acre in these tests. Nitrogen had greater effect on yields than phosphorus, however, maximum yields were realized by using a combination of nitrogen and phosphorus as a fertilizer. Darker green color intensity was obtained with higher rates of fertilizer. Higher rates of phosphorus have a tendency to suppress the bushel weight. The highest net dollar return was obtained by using 150 lbs of nitrogen and 30 lbs of phosphorus per acre.