Abstract: Different length of cellulose fiber, PPTA-pulp fiber and mineral wool fiber was sieved by Bauer-McNett classifier and the weight average fiber length was measured. The compressibility and resilience properties of non-asbestos sealing gasket made by beater-addition process were tested by U₈(4³) homogenous experimental design. The relationship of compressibility ratio and resilience ratio and fiber length was studied by multi-linear regression which was used to predict compressibility and resilience properties. The predicted values were compared with experimental values. The results show that fiber length had a significant effect on compressibility and resilience properties. The compressibility ratio increased and resilience ratio decreased with increase of fiber length. The effect of fiber length of PPTA-pulp was the most significant. The predicted values by regression equation were approximately equal to experimental values.