  We propose a way to generate the electroweak symmetry breaking radiatively in
non-supersymmetric type I models with string scale in the TeV region. By
identifying the Higgs field with a tree-level massless open string state, we
find that a negative squared mass term can be generated at one loop. It is
finite, computable and typically a loop factor smaller than the string scale,
that acts as an ultraviolet cutoff in the effective field theory. When the
Higgs open string has both ends confined on our world brane, its mass is
predicted to be around 120 GeV, i.e. that of the lightest Higgs in the minimal
supersymmetric model for large $\tan\beta$ and $m_A$. Moreover, the string
scale turns out to be one to two orders of magnitude higher than the weak
scale. We also discuss possible effects of higher order string threshold
corrections that might increase the string scale and the Higgs mass.
