The role played by the Y-family DNA polymerases YqjH and YqjW in protecting sporulating cells of Bacillus subtilis from DNA damage was determined. The absence of either yqjH and/or yqjW not only reduced sporulation efficiency but also sensitized the sporulating cells to hydrogen peroxide, tert-butylhydroperoxide (t-BHP), mitomycin-C (M-C), and UV-C radiation. Moreover, these DNA-damaging agents increased the mutation frequency of wild-type sporulating cells to 4-azaleucine, but the production of mutants was YqjH- and YqjW-dependent. In conclusion, the results presented here indicate that YqjH/YqjW-dependent-translesion synthesis (TLS) operates in sporulating B. subtilis cells and contributes in processing spontaneous and artificially induced genetic damage, which is apparently required for an efficient sporulation process.