This book constitutes the refereed proceedings of the 14th International Conference on Tests and Proofs, TAP 2020, held as part of the 4th World Congress on Formal Methods 2020, Bergen, Norway, in June 2020.The 7 regular papers, 1 short paper and 2 demonstration papers presented in this volume were carefully reviewed and selected from 209 submissions. The TAP conference promotes research in verification and formal methods that targets the interplay of proofs and testing: the advancement of techniques of each kind and their combination, with the ultimate goal of improving software and system dependability.