  The result of the OPERA experiment revealed that the velocity of
muon-neutrinos was larger than the speed of light. We argue that this apparent
superluminal velocity can be interpreted as a weak value, which is a new
concept recently studied in the context of quantum physics. The OPERA
experiment setup forms a scheme that manifests the neutrino velocity as a weak
value. The velocity defined in the scheme of weak measurement can exceed the
speed of light. The weak velocity is not a concept associated to a single
phenomenon but it is a statistical concept defined by accumulating data at
separated places and by comparing the data. Neither information nor physical
influence is conveyed at the weak velocity. Thus the superluminal velocity in
the sense of weak value does not contradict the causality law. We propose also
a model for calculating the neutrino velocity with taking neutrino oscillation
into account.
