  Large-$N$ renormalization group equations for one- and two-matrix models are
derived. The exact renormalization group equation involving infinitely many
induced interactions can be rewritten in a form that has a finite number of
coupling constants by taking account of reparametrization identities. Despite
the nonlinearity of the equation, the location of fixed points and the scaling
exponents can be extracted from the equation. They agree with the spectrum of
relevant operators in the exact solution. A linearized $\beta$-function
approximates well the global phase structure which includes several nontrivial
fixed points. The global renormalization group flow suggests a kind of
$c$-theorem in two-dimensional quantum gravity.
