Non-lethal genetic surveys in insects usually extract DNA from a leg or a piece of wing. Although preferable to lethal sampling, little is known about the effect of leg/wing non-lethal sampling on fitness-related traits. 2. Graellsia isabelae (Graells, 1849) is a European moth protected by the Habitats Directive and the Bern Convention. Conservation genetics surveys on this species should therefore use non-lethal sampling. 3. The present study aimed to (1) quantify the effects of both leg and hind-wing tail sampling on survivorship and reproductive behaviour of adult males and females, and (2) assess the quality and quantity of DNA obtained from those tissues. 4. Both hind-wing tails and mid-legs proved to be good sources of high quality nuclear and mitochondrial DNA. DNA concentration was significantly higher when extracted from a large (130 mm 2 ) piece of the hind-wing tails than from about half of the mid-leg. Using mark – release – recapture experiments with adults, it was found that neither midleg nor hind-wing tail sampling significantly reduced male survivorship or total number of matings. However, although mid-leg sampling did not significantly affect female survivorship, it had a negative effect on female mating success. 5. Wing-tail clipping on males appeared to be the best non-lethal sampling procedure for G. isabelae . It is a fast procedure, similar to natural wing impairment, and did not significantly affect survival or mating behaviour.