In this article, the B spline technique is employed to calculate the energy values of a number of low-lying states of hydrogen atom in the presence of a homogeneous magnetic field of arbitrary strength (０＜Ｂ≤４．７×１０8T) our results fill the gaps in the results of the works by Rosner et al. and Ivanov, and agree well with those obtained by other theoretical calculations. B spline functions are proved to be powerful in treating the excited, as well as ground states of hydrogen in magnetic field.