This study aims to get a better understanding of the oviposition-behaviour of the butterflyMarsh Fritillary (Euphydryas aurinia), in the area Bälsalvret on the Island of Gotland. Thestudy may provide helpful information to aid the conservation of the species in the area andalso provide overall knowledge about the female’s preferences when it comes to choosingmicrohabitat and host plant for their eggs.The analysis of the microhabitat preference for oviposition by the Marsh Fritillary showedthat eggs were predominantly laid on large-sized host plant individuals with a warmermicroclimate; with a preference for the rosette diameter, the length and the width of the leafand the number of Succisa pratensis individuals in the vicinity. This indicates that thefemale’s priority is to place the eggs at the most optimal place for their offspring’s survivaland growth.