We recalculate the pion electromagnetic form factor based on the pertu
rbative QCD formalism that includes the Sudakov resummation. We take i
nto account the evolution of the pion wave function in b, which repres
ents the transverse extent of the pion. An infrared enhancement is obs
erved when 1/b approaches Lambda(QCD). We propose to freeze the evolut
ion of the wave function at some scale above Lambda(QCD), such that pe
rturbative contributions are stablized. Our predictions are consistent
with experimental data, and insensitive to the variation of relevant
parameters.