We investigate equilibrium statistical properties of urn models with disorder. The model is introduced from the view point of the power-law behavior and randomness; it is clarified that quenched random parameters play an important role in generating power-law behavior.We evaluate the occupation probability P(k) with which an urn has k balls by using the concept of statistical physics of disordered systems. In the disordered urn model belonging to the Monkey class, we find that above critical density ρc for a given temperature, condensation phenomenon occurs and the occupation probability changes its scaling behavior from an exponentiallaw to a heavy tailed power-law in large k regime. We also discuss an interpretation of our results for explaining of macro-economy, in particular, emergence of wealth differentials.