Abstract: The three velocity components and air temperature weremeasured using a triaxial ultrasonic anemometer in Hefei region of China.The mean dissipation rates of turbulent kinetic energy \varepsilon and1/2 temperature variance \varepsilon _\theta have been estimated byKolmogorov's `four-fifths' law and Yaglom's `four-thirds' law, respectively.It is pointed that the traditional method is not suitable for estimatinginner scale of temperature field. A new relation between the inner scale oftemperature field and 1/2 temperature variance \varepsilon _\theta ispresented. The results of estimating inner scale by the new proposed methodperfectly show that strong turbulence has small inner scales and weakturbulence larger inner scales.