diff --git a/doc/reference/logging/index.rst b/doc/reference/logging/index.rst
index 27f5d2e253a..b909ed0fe59 100644
--- a/doc/reference/logging/index.rst
+++ b/doc/reference/logging/index.rst
@@ -50,6 +50,12 @@ Logging v2 introduces following changes:
 - No change in logging API
 - Logging backend API exteded with function for processing v2 messages.
 
+.. note::
+   Logging v1 is deprecated! Version 2 supports same set of features with listed
+   above extensions. However, logging backend API is different. All backends in
+   the tree support version 2 API. Any custom backend must be adapted to version 2.
+   Version 1 support will be removed after 3.1 release.
+
 Logging API is highly configurable at compile time as well as at run time. Using
 Kconfig options (see :ref:`logging_kconfig`) logs can be gradually removed from
 compilation to reduce image size and execution time when logs are not needed.