The central aim of evolutionary biology is to understand patterns of genetic variation between species and within populations. To quantify the genetic variation underlying intraspecific differences, estimating quantitative genetic parameters of traits is essential. In Pterygota, wing morphology is an important trait affecting flight ability. Moreover, gregarious parasitoids such as Nasonia vitripennis oviposit multiple eggs in the same host, and siblings thus share a common environment during their development. Here we estimate the genetic parameters of wing morphology in the outbred HVRx population of N. vit-ripennis, using a sire-dam model adapted to haplodiploids and disentangled additive genetic effects and host effects. The results show that the wing size traits have low heritability (h2~0.1), while most wing shape traits have roughly twice the heritability compared to wing size traits. However, the estimates in-creased to h2~0.6 for wing size traits when omitt ing the host effect from the statistical model, while no meaningful increases were observed for wing shape traits. Overall, host effects contributed ~50% of the variation in wing size traits. This indicates that hosts have a large effect on wing size traits, about five-fold more than genetics. Moreover, bivariate analyses were conducted to derive the genetic relationships among traits. Overall, we demonstrate the evo-lutionary potential for morphological traits in the N. vitripennis HVRx outbred population and report the host effects on wing morphology. Our findings can contribute to a further dissection of the genetics underlying wing morphology in N. vitripennis, with relevance for gregarious parasitoids and possible other insects as well.