  We propose a chiral random matrix model which properly incorporates the
flavor-number dependence of the phase transition owing to the \UA(1) anomaly
term. At finite temperature, the model shows the second-order phase transition
with mean-field critical exponents for two massless flavors, while in the case
of three massless flavors the transition turns out to be of the first order.
The topological susceptibility satisfies the anomalous \UA(1) Ward identity and
decreases gradually with the temperature increased.
