B-spline functions have been widely used in computational atomic physics. Different from the traditional B-spline basis (a simple product of two B-splines), the recently developed correlated B-spline basis functions(C-BSBF), in which the interelectronic coordinate r12 is included explicitly, have greatly improved the computational accuracy of polarizability [S. J. Yang et al., Phys. Rev. A 95, 062505 (2017)] and bethe logarithm [ S. J. Yang et al., Phys. Rev. A 100, 042509 (2019)] for singlet states of helium. Here, we report the extension of the C-BSBF to the leading relativistic and QED correction calculations for energy levels of the 1 1 S, 2 1 S, 2 3 S, and 3 3 S states of helium. The relativistic kinetic term p 4 1 , contact potential δ 3 (r1), δ 3 (r12) and Araki-Sucher correction 1/r 3 12 are calculated by using the global operator method, in which r n 12 and r n 12 ln r12 involved are calculated with the generalization of Laplace's expansions. The obtained values for the ground state are δE rel /α 2 = −1.951 754 7(2) and δEQED/α 3 =57.288 165(2), consistent with previous results, which opens the possibility of calculating higher-order relativistic and QED effects using the C-BSBF.