The main objective of this paper is to proceed an outcome evaluation of the ?FatorPrevidenciário? Law. The ?Fator Previdenciário? has been introduced by Law 9.876of November 1998. The evaluation has been done in two ways: outcome gauge of fatorprevidenciário?s application on the transition period of 1999/2004 by means ofhypothesis test; and investigation of the law compatibility with ?general interest?of social security policy.By these analysis, it has been verified that both age and time of contribution tosocial security system have increased; nevertheless, the benefits values have decreasedfor those which have retired by contribution time (APCs).As a corollary of the outcomes above, it has been also observed a significanteconomy to the Social Security public expenses (or bill) in relation to the ?APCs??sflux of grant.