The dynamic moduli of elasticity (moduli of longitudinal and transverse elasticity) and Poisson's ratio of aluminum wrought alloys were measured in the temperature range of 20 400°C by ultrasonic reflection method originated by the authors to examine their dependence on temperature.The results showed that the both elastic moduli tended to decrease with the rise of temperature. The rate of decrease was slow up to about 100°C and became much higher at 200 300°C. In the range of these experiments, the materials showing great temperature dependences of elastic moduli were 1100-O, 2011-T3, 2040-O, 7075-T6, and in particular, 2017-O. On the other hand, the materials showing considerably less temperature dependences were 2014-T6, 2017-T4, 5056-O, 7075-O and in particular, 2024-T4. The elastic moduli differed with different materials and also much differed with different heat treatments of the same material.In the range of experiments, the materials having large moduli at room temperature were 2011-T3, 2014-O, 2014-T6, 2024-O, 2024-T6, 7075-O, 7075-T6, etc.;and the materials showing considerably smaller moduli were 1100-O, 2017-T4, 5656-O, etc.The Pisson's ratio showed no significant differences among the materials, even though it was relatively larger in 2014-T6, 5056-O and in particular, 7075-T6. Though there was slight increase of the ratio with the rise of temperature in a few materials, its temperature dependence was hardly observed.