Abstract: A procedure for measuring the relative quantities of pulp components in wood or paper pulp, whereinfor the pulp components (a,b) present in the pulp, for each one separately, is measured the distribution, or probability density, function (b.sub.a, b.sub.b) of a given fibre-specific characteristic thereof,from the distribution functions are by calculation formed distribution functions (b.sub.a/b) corresponding to the pulp mixture,the distribution function (b.sub.x/y) of the corresponding characteristic of the pulp is measured, andby calculation are determined the correlations of the distribution function (b.sub.x/y) of the pulp under examination with the distribution functions (b.sub.a/b) found by calculation, for determining the proportions of the different pulp components.