diff --git a/lib/bundler/yaml_serializer.rb b/lib/bundler/yaml_serializer.rb
index 37ccc46c26..abc931dc67 100644
--- a/lib/bundler/yaml_serializer.rb
+++ b/lib/bundler/yaml_serializer.rb
@@ -56,6 +56,7 @@ module Bundler
       last_hash = nil
       last_empty_key = nil
       str.split(/\r?\n/) do |line|
+        line = line.split("#", 2).first.strip if line.include?("#")
         if match = HASH_REGEX.match(line)
           indent, key, quote, val = match.captures
           convert_to_backward_compatible_key!(key)
diff --git a/lib/rubygems/yaml_serializer.rb b/lib/rubygems/yaml_serializer.rb
index 947fda0911..7555c83d6b 100644
--- a/lib/rubygems/yaml_serializer.rb
+++ b/lib/rubygems/yaml_serializer.rb
@@ -56,6 +56,7 @@ module Gem
       last_hash = nil
       last_empty_key = nil
       str.split(/\r?\n/) do |line|
+        line = line.split("#", 2).first.strip if line.include?("#")
         if match = HASH_REGEX.match(line)
           indent, key, quote, val = match.captures
           convert_to_backward_compatible_key!(key)
diff --git a/spec/bundler/bundler/yaml_serializer_spec.rb b/spec/bundler/bundler/yaml_serializer_spec.rb
index 913b0235b8..0b2c8e167c 100644
--- a/spec/bundler/bundler/yaml_serializer_spec.rb
+++ b/spec/bundler/bundler/yaml_serializer_spec.rb
@@ -174,6 +174,21 @@ RSpec.describe Bundler::YAMLSerializer do
 
       expect(serializer.load(yaml)).to eq(hash)
     end
+
+    it "skip commented out words" do
+      yaml = <<~YAML
+        ---
+        foo: "bar"
+        buzz: # "foo"
+      YAML
+
+      hash = {
+        "foo" => "bar",
+        "buzz" => {},
+      }
+
+      expect(serializer.load(yaml)).to eq(hash)
+    end
   end
 
   describe "against yaml lib" do
diff --git a/spec/bundler/commands/config_spec.rb b/spec/bundler/commands/config_spec.rb
index 547fd2d869..c849384ff2 100644
--- a/spec/bundler/commands/config_spec.rb
+++ b/spec/bundler/commands/config_spec.rb
@@ -439,7 +439,7 @@ E
     it "does not make bundler crash and ignores the configuration" do
       bundle "config list --parseable"
 
-      expect(out).to eq("#mirror.https://rails-assets.org/=http://localhost:9292")
+      expect(out).to be_empty
       expect(err).to be_empty
 
       ruby(<<~RUBY)