We construct a modular generalized Springer correspondence for any classical group, by generalizing to the modular setting various results of Lusztig in the case of characteristic-$0$ coefficients. We determine the cuspidal pairs in all classical types, and compute the correspondence explicitly for $mathrm{SL}(n)$ with coefficients of arbitrary characteristic and for $mathrm{SO}(n)$ and $mathrm{Sp}(2n)$ with characteristic-$2$ coefficients.