This volume contains the papers of the 9th International Conference on Typed Lambda Calculi and Applications (TLCA 2009), which was held from July 1–3, 2009, in Bras´ ?lia, Brazil, as part of the 5th International Conference on Rewr- ing, Deduction, and Programming (RDP 2009) together with the International Conference on Rewriting Techniques and Applications (RTA 2009), the Inter- tionalSchoolonRewriting(ISR2009),the4thWorkshoponLogicalandSem- ticFrameworkswithApplications(LSFA2009),the10thInternationalWorkshop on Rule-Based Programming (RULE 2009), the 8th International Workshop on Functionaland(Constraint)LogicProgramming(WFLP 2009),the9thInter- tional Workshop on Reduction Strategies in Rewriting and Programming (WRS 2009),andtheannualmeetingoftheIFIPWorkingGroup1.6ontermrewriting. The TLCA series of conferences serves as a forum for presenting original research results that are broadly relevant to the theory and applications of lambda-calculus. Typed lambda-calculi are underlying programming language semantics and implementation on one hand, and a large part of proof theory on the other hand. Previous TLCA conferences were held in Utrecht (1993), Ed- burgh (1995), Nancy (1997), L’Aquila (1999), Krak´ ow (2001), Valencia (2003), Nara (2005), and Paris (2007). For TLCA 2009, 27 papers were accepted out of 53 submissions. Each - per was reviewed by at least three members of the Program Committee, with the help of 84 external reviewers. I would like to thank the members of the Program Committee and the external reviewers for their great work, as well as Andrei Voronkov for providing the EasyChair system which was invaluable in the reviewing process, the electronic Program Committee meeting, and the preparation of this volume.