This book constitutes the proceedings of the 10th Latin American Symposium on Theoretical Informatics, LATIN 2012, held in Arequipa, Peru, in April 2012. The 55 papers presented in this volume were carefully reviewed and selected from 153 submissions. The papers address a variety of topics in theoretical computer science with a certain focus on algorithms, automata theory and formal languages, coding theory and data compression, algorithmic graph theory and combinatorics, complexity theory, computational algebra, computational biology, computational geometry, computational number theory, cryptography, theoretical aspects of databases and information retrieval, data structures, networks, logic in computer science, machine learning, mathematical programming, parallel and distributed computing, pattern matching, quantum computing and random structures.