  The electroweak gauge symmetry is allowed to be spontaneously broken by the
strongly interacting vector-like gauge dynamics. When the gauge coupling of a
theory runs slowly in a wide range of energy scale, the theory is a candidate
for walking technicolor. This may open up the possibility that the origin of
all masses may be traced back to the gauge theory. We use the \SF method to see
whether the gauge coupling of 10-flavor QCD "walks" or not. Preliminary result
is reported.
