This book constitutes revised selected papers from the 22nd International Symposium on Trends in Functional Programming, TFP 2021, which was held virtually in February 2020.The 6 full papers presented in this volume were carefully reviewed and selected from 18 submissions. They were organized in topical sections about nested parallelism, semantics, task-oriented programming and modelling, translating, proving functional programs.Chapter ‘Dataset Sensitive Autotuning of Multi-Versioned Code based on Monotonic Properties’ is available open access under a Creative Commons Attribution 4.0 International License via link.springer.com. Chapter ‘High-level Modelling for Typed Functional Programming’ is available open access under a Creative Commons Attribution 4.0 International License via link.springer.com.