Analytical formula for multiplicity distribution is derived in the QO approach, where chaotic and coherent fields are contained. Observed charged multiplicity distributions in Au+Au collisions at $sqrt{s}=200$ AGeV and in pp collisions at $sqrt{s}=900$ GeV are analyzed by the formula. Chaoticity parameters in the inclusive events estimated from the analysis of multiplicity distributions are compared with those estimated from the analysis of observed two-particle inclusive identical particle correlations.