We study the scaling behavior of the characteristic length of precursor magnetic nanostructures above the Curie temperature with the correlation length of quenched-in disorder. We found that the modulation length of the nanostructures follows the scaling law D ¯ , where Dis the average size of the magnetized regions in the material. The scaling behavior of the average size of these regions, D¯ , with the correlation length of the disorder, , depends on the properties of the disorder. For Gaussian disorder, we find that Dscales with the disorder correlation length as D a/2 , where a is the exponent of the leading term of the pair correlation function of the disorder in the limit r → 0, r 1� 1/ ar / a . These results are quite general and applicable to other systems, e.g., ferroelectric precursors, independent of the nature of the long-range dipolar forces.