diff --git a/installation/install-by-gem.md b/installation/install-by-gem.md
index cbd02214..59441b17 100644
--- a/installation/install-by-gem.md
+++ b/installation/install-by-gem.md
@@ -8,7 +8,7 @@ Please follow the [Pre-installation Guide](before-install.md) to configure your
 
 ## Step 1: Install Ruby Interpreter
 
-Install Ruby `>= 2.7` on your local environment. In addition, install `ruby-dev` package via Package Manager to build native extension gems.
+Install Ruby `>= 3.3` on your local environment. In addition, install `ruby-dev` package via Package Manager to build native extension gems.
 
 ## Step 2: Install Fluentd Gem
 
diff --git a/installation/install-from-source.md b/installation/install-from-source.md
index 71174909..df3a49f5 100644
--- a/installation/install-from-source.md
+++ b/installation/install-from-source.md
@@ -4,7 +4,7 @@ This article explains how to install Fluentd from source \(git repository\). Thi
 
 ## Step 1: Install Ruby Interpreter
 
-Install Ruby `>= 3.2` and `bundler` on your local environment.
+Install Ruby `>= 3.3` and `bundler` on your local environment.
 
 ## Step 2: Fetch Source Code
 
diff --git a/quickstart/faq.md b/quickstart/faq.md
index 64eaf0b2..9ed17b41 100644
--- a/quickstart/faq.md
+++ b/quickstart/faq.md
@@ -2,9 +2,9 @@
 
 ## Which version of Ruby does `fluentd` support?
 
-The latest fluentd works on Ruby 3.2 or later.
+The latest fluentd works on Ruby 3.3 or later.
 
-Though the minimum required version is Ruby 3.2 or later, we recommend using `fluentd` with a
+Though the minimum required version is Ruby 3.3 or later, we recommend using `fluentd` with a
 newer stable version.
 
 ## What is the difference between v1 and v0.14?