Thin stainless steel sheets hold considerable promise for improving several properties of aluminium based fibre metal laminates (FMLs). To allow incorporation of such sheets in FMLs their adhesion to epoxies used in aerospace applications should be at a high level. The present work describes the effects of chemical and mechanical pretreatments to regular and molybdenum-enriched AISI 301 steel sheets. Based on an in-depth knowledge of aluminium pretreatment for FML applications, also aluminium-coated stainless-steel sheets are investigated. Gritblasting was found to yield the best properties. The effect of coating the steel surface with aluminium was found to be promising, but the bond strength between the aluminium and the steel substrate proved insufficient for thin (0.1 mm) AlSl 301 steel sheet.