  We have calculated the Bjorken-x dependence of the kaon and pion valence
quark distributions in a statistical model. Each meson is described by a Fock
state expansion in terms of quarks, antiquarks and gluons. Although Drell-Yan
experiments have measured the pion valence quark distributions directly, the
kaon valence quark distributions have only been deduced from the measurement of
the ratio $\bar{u}_K(x)/\bar{u}_\pi(x)$. We show that, using no free
parameters, our model predicts the decrease of this ratio with increasing x.
