diff --git a/README.md b/README.md
index b0b27d1f..2258759a 100644
--- a/README.md
+++ b/README.md
@@ -5,6 +5,10 @@
 **ruma-api** contains core types used to define the requests and responses for each endpoint in the various [Matrix](https://matrix.org/) API specifications.
 These types can be shared by client and server code for all Matrix APIs.
 
+## Minimum Rust version
+
+ruma-api requires Rust 1.34 or later.
+
 ## Documentation
 
 ruma-api has [comprehensive documentation](https://docs.rs/ruma-api) available on docs.rs.