The multifractality of energy and thermal dissipation of fully developed intermittent turbulence in the urban canopy layer is investigated by the singularity spectrum. An ultrasonic anemometer with a high sampling frequency of 100 Hz was used to obtain high-order moment properties. The authors found that the singular exponents of energy and thermal dissipation rates are most frequently encountered at around 0.2, which is significantly smaller than those for a wind tunnel at a moderate Reynolds number. The evidence indicates a higher intermittency of turbulence at a high Reynolds number. Furthermore, the temperature field is more intermittent than the velocity field.