In Chernobyl, chronic exposure to radioactive contaminants has a variety of deleterious effects on exposed organisms, including genetic damage and mutation accumulation. The potential for such effects to be transmitted to the next generation is however poorly understood. We captured lesser marsh grasshoppers (Chorthippus albomarginatus) in the Chernobyl Exclusion Zone from sites varying in levels of environmental radiation by more than three orders of magnitude. We then raised their offspring in a common garden experiment in order to assess the effects of parental exposure to radiation on offspring development and DNA damage. Offspring that reached maturity at a younger age had higher levels of DNA damage. Contrary to our hypothesis, parental exposure to radioactive contamination did not affect DNA damage in their offspring, possibly due to intervening adaptation or to parental compensatory mechanisms. In addition, lower average DNA damage within a family was associated with higher survival in that family. Our results suggest a trade-off between developmental rate and resistance to DNA damage whereby offspring developing at faster rates do so at the cost of damaging their DNA. This result is consistent with and extends findings in other species suggesting that faster growth rates cause increased oxidative damage and stress. We propose that growth rates are subject to stabilizing selection balancing the benefits of fast development and the competing need of buffering its damaging effects to macromolecules and tissues.