Waveguide dispersion characteristics of two kinds of triple-cladding single-mode fibers named WⅠ and WⅡ is discussed. According to authors′ research, it is concluded that the range of the zero dispersion point of the WⅠ-and WⅡ-type single-mode fibers is obviously larger than that of the conventional W-type single-mode fibers under the same condition. The influences of the geometric parameters P, Q and optical parameters R 1, R 2 on the waveguide dispersion and cutoff frequency of low order modes for WⅠ-and WⅡ-type fibers are analyzed. The result provides a significant reference for the designs of new types of dispersion-flattened fiber, dispersion-shifted fiber and passive optical devices. The method to calculate waveguide dispersion can be applied to multi-cladding fibers.