Up to the present, all lists of Portuguese Lepidoptera have been a chaotic mixture of genuine records and misidentifications together with errors of omission and inclusion, with no means of distinguishing good from bad. In Lepidoptera of Continental Portugal the source data for the first published record is given for each of the 2588 accepted Portuguese species. There is also a list of 398 rejected species. Basic distribution data is given for every species, together with flight times and food plant information where known. The list is the result of 25 years of investigation of the Portuguese Lepidoptera by the author, involving field work in many parts of the country, together with study of all relevant literature and examination of recent and historic collections. The list should provide a firm foundation for future work on all aspects of the biology and conservation of Portuguese Lepidoptera and allow the publication of identification handbooks. Colour photographs of some characteristic habitats.