Abstract: This paper illustrates.how homogeneous function, analysis can be. generalized to relativistic quantum mechanics for finding the WKB energy levels of Dirac particle in the positive power-law potentials (V=λr^v, S=λr'^v, λ, λ', v>0). The results show that the equation determining energy levels contains a product of hypergeometric function with some gamma functions, and the energy of particle is proportional to (2n_r+l+3/2)^(2v/1+v) under the condition that the relativistic effect plays a principal role in contrast with the (2n_r+l+3/2)^(2v/2+v) dependence in nonrelativistic case.