Despite mating representing a mutual interaction, the study of mate preferences has long focussed on choice in one sex and on the preferred traits in the other. This has certainly been true in the study of the costs and condition-dependent expression of mating preferences, with the majority of studies concerning female preference. The condition-dependence and genetic architecture of mutual mate preferences remain largely unstudied, despite their likely relevance for the evolution of preferences and of mating behavior more generally. Here, we measured (i) male and female mate preferences and (ii) intersexual genetic correlations for the mating activity in pedigreed populations of southern field crickets (Gryllus bimaculatus) raised on a favourable (free-choice) or stressful (protein-deprived) diet. In the favourable dietary environment, mutual mate preferences were strong, and the intersexual genetic covariance for mating activity was not different from one. However, in the stressful dietary environment, mutual mate preferences were weak, and the intersexual genetic covariance for mating activity was significantly smaller than one. Altogether, our results show that diet environments affect the expression of genetic variation in mating behaviors: (i) the strength of mutual mate preference and (ii) intersexual genetic covariance for mating activity tend to be weaker when environment is stressful. This implies that mating dynamics strongly vary across environments.