Abstract: Considering the thermal expansion coefficient and elastic modulus of CNTs(carbon nanotubes)as functions of temperature,and the coefficient of thermal expansion,coefficient of moisture expansion and elastic modulus of matrix as functions of temperature and moisture,the effects of hygrothermal environment on interfacial stress transfer of CNT composites are investigated using classical elastic shell theory and conventional fiber pullout models.Numerical examples show that the interfacial shear stress transfer behavior can be obviously affected by several parameters such as temperature,moisture and CNT layer numbers.