Soybean varieties have been developed with modified fatty acid profiles to address different healthy food and industrial uses of the oil. The objectives of this study were to determine the effects of temperature on fatty acid composition in soybeans with modified fatty acid (MFA) profile using a controlled environment and field experiments. In the controlled environment experiment, seven soybean lines were grown under three different day/night temperature regimes: warm (30/25°C), medium (25/20°C), and low (20/15°C). The low temperature produced significantly lower oleic acid concentration than both the warm and medium regimes. Date of planting treatments were used to create different growing environments for six MFA soybean lines in the field. The results demonstrated that high temperatures produced the highest levels of oleic acid in soybean seeds in both the field and controlled environments study. The planting dates did not have a significant effect on oleic acid levels but locations did.