  We apply the probability distribution function method to the study of chiral
properties of QCD with quarks in the exact massless limit. A relation among the
chiral condensate, zeros of the Bessel function and eigenvalue of Dirac
operator is also given. The chiral condensate in this limit can be measured
with small number of eigenvalues of the massless Dirac operator and without any
ambiguous mass extrapolation. Results for SU(3) gauge theory with quenched
Kogut-Susskind quarks on the $10^4$ lattice are shown.
