This book constitutes the thoroughly refereed post-conferenceproceedings of the 13th Brazilian Symposium on Formal Methods, SBMF2010, held in Natal, Brazil, in November 2010.The 18 revised full papers were carefully reviewed and selected from55 submissions. The papers presented cover a broad range of foundationaland methodological issues in formal methods for the design and analysisof software and hardware systems as well as applications in variousdomains.