  We study the asymptotic behavior of the $B$ meson wave function in the
framework of $k_T$ factorization theorem. We first construct a definition of
the $k_T$-dependent $B$ meson wave function, which is free of light-cone
divergences. Next-to-leading-order corrections are then calculated based on
this definition. The treatment of different types of logarithms in the above
corrections, including the Sudakov logarithms, and those depending on a
renormalization scale and on an infrared regulator, is summarized. The
criticism raised in the literature on our resummation formalism and Sudakov
effect is responded. We show that the $B$ meson wave function remains
normalizable after taking into account renormalization-group evolution effects,
contrary to the observation derived in the collinear factorization theorem.
