diff --git a/README.md b/README.md
index b8d067ffb7a..11e69c5e593 100644
--- a/README.md
+++ b/README.md
@@ -37,6 +37,8 @@ Releases can be downloaded from [official website](https://www.dolibarr.org/).
 
 You can use a Web server and a supported database (MariaDB, MySQL or PostgreSQL) to install the standard version.
 
+- Check that your installed PHP version is supported [see PHP support](./doc/phpmatrix.md).
+
 - Uncompress the downloaded .zip archive to copy the "dolibarr/htdocs" directory and all its files inside your web server root or get the files directly from GitHub (recommanded if you known git):
 
   `git clone https://github.com/dolibarr/dolibarr -b x.y`     (where x.y is main version like 3.6, 9.0, ...)
@@ -68,6 +70,7 @@ If you don't have time to install it yourself, you can try some commercial 'read
 ## UPGRADING
 
 - At first make a backup of your Dolibarr files & than see https://wiki.dolibarr.org/index.php/Installation_-_Upgrade#Upgrade_Dolibarr
+- Check that your installed PHP version is support by the new version [see PHP support](./doc/phpmatrix.md).
 - Overwrite all old files from 'dolibarr' directory with files provided into the new version's package.
 - At first next access, Dolibarr will redirect your to the "install/" page to follow the upgrade process.
   If an `install.lock` file exists to lock any other upgrade process, the application will ask you to remove the file manually (you should find the `install.lock` file into the directory used to store generated and uploaded documents, in most cases, it is the directory called "*documents*").