Based on the coupled-mode theory and the relation between Jones matrix and Stokes vector, we give the formulas for reflected and transmitted Stokes parameters of low-birefringence single-mode uniform optical fiber Bragg grating (FBG). The curves of reflected and transmitted Stokes parameters versus wavelength of low-birefringence single-mode uniform FBG are simulated under different birefringence values. The results show that: among the four normalized Stokes parameters, s1 is antisymmetric about the central wavelength λ0, S0, s2 and s3 are symmetric about λ0. Although spectral lines do not produce a drift, the bandwidth of reflected signals is narrowed with the growing of birefringence values. The Stokes amplitudes of reflected and transmitted signals have different changes. It is shown that birefringence values have significant influences on Stokes parameters. The curves of reflected and transmitted Stokes parameters versus the parameters of single-mode uniform FBG are measured. The theoretical analysis and experimental results coincide with each other.