This book constitutes the refereed proceedings of the 5th International Conference on Pattern Recognition in Bioinformatics, PRIB 2010, held in Nijmegen, The Netherlands, in September 2010.The 38 revised full papers presented were carefully reviewed and selected from 46 submissions. The field of bioinformatics has two main objectives: the creation and maintenance of biological databases and the analysis of life sciences data in order to unravel the mysteries of biological function. Computer science methods such as pattern recognition, machine learning, and data mining have a great deal to offer the field of bioinformatics. The ?eld of bioinformatics has two main objectives: the creation and main- nance of biological databases and the analysis of life sciences data in order to unravel the mysteries of biological function. Computer science methods such as patternrecognition,machinelearning,anddatamining haveagreatdealtoo?er the ?eld of bioinformatics. The Pattern Recognition in Bioinformatics (PRIB) meeting was established in 2006 under the auspices of the International Asso- ation of Pattern Recognition (IAPR) to create a focus for the application and development of computer science methods to life science data. The 5th PRIB conference was held in Nijmegen, The Netherlands, on 22¿24 September 2010. A total of 46 papers were submitted to the conference for peer review. Of those, 38 (83%) were accepted for publication in these proceedings. The invited speakers were Rita Casadio (Bologna Biocomputing Group, Italy), Florence d¿Alch¿ e-Buc (Universit¿ e d¿Evry-Val d¿Essonne, France), Daniel - son (Tu ¿bingen University, Germany), and Natasa Przulj (Imperial College L- don, UK). Tutorials weredeliveredby Concettina Guerra (Universit` adi Padova, Italy), Clarisse Dhaenens (Laboratoire LIFL/INRIA, France), Laetitia Jourdan (Laboratoire LIFL/INRIA, France), Neil Lawrence (University of Manchester, UK), and Dick de Ridder (Delft University of Technology).