diff --git a/README.md b/README.md
index f565713f..407da7e4 100644
--- a/README.md
+++ b/README.md
@@ -305,6 +305,7 @@ But if you wish to select or exclude specific linters, we give you full control
 | **MARKDOWN_CUSTOM_RULE_GLOBS**     | `.markdown-lint/rules,rules/**` | Comma-separated list of [file globs](https://github.com/igorshubovych/markdownlint-cli#globbing) matching [custom Markdownlint rule files](https://github.com/DavidAnson/markdownlint/blob/main/doc/CustomRules.md). |
 | **NATURAL_LANGUAGE_CONFIG_FILE**   | `.textlintrc`                   | Filename for [textlint configuration](https://textlint.github.io/docs/getting-started.html#configuration) (ex: `.textlintrc`)                                                                                        |
 | **PHP_CONFIG_FILE**                | `php.ini`                       | Filename for [PHP Configuration](https://www.php.net/manual/en/configuration.file.php) (ex: `php.ini`)                                                                                                               |
+| **PROTOBUF_CONFIG_FILE**           | `.protolintrc.yml`              | Filename for [protolint configuration](https://github.com/yoheimuta/protolint/blob/master/_example/config/.protolint.yaml) (ex: `.protolintrc.yml`)                                                                                                                                                    |
 | **PYTHON_BLACK_CONFIG_FILE**       | `.python-black`                 | Filename for [black configuration](https://github.com/psf/black/blob/main/docs/guides/using_black_with_other_tools.md#black-compatible-configurations) (ex: `.isort.cfg`, `pyproject.toml`)                          |
 | **PYTHON_FLAKE8_CONFIG_FILE**      | `.flake8`                       | Filename for [flake8 configuration](https://flake8.pycqa.org/en/latest/user/configuration.html) (ex: `.flake8`, `tox.ini`)                                                                                           |
 | **PYTHON_ISORT_CONFIG_FILE**       | `.isort.cfg`                    | Filename for [isort configuration](https://pycqa.github.io/isort/docs/configuration/config_files.html) (ex: `.isort.cfg`, `pyproject.toml`)                                                                          |
diff --git a/lib/linter.sh b/lib/linter.sh
index ca0a0e5f..8b91bf11 100755
--- a/lib/linter.sh
+++ b/lib/linter.sh
@@ -144,7 +144,7 @@ PHP_PSALM_FILE_NAME="psalm.xml"
 # shellcheck disable=SC2034  # Variable is referenced indirectly
 POWERSHELL_FILE_NAME=".powershell-psscriptanalyzer.psd1"
 # shellcheck disable=SC2034  # Variable is referenced indirectly
-PROTOBUF_FILE_NAME=".protolintrc.yml"
+PROTOBUF_FILE_NAME="${PROTOBUF_CONFIG_FILE:-.protolintrc.yml}"
 # shellcheck disable=SC2034  # Variable is referenced indirectly
 PYTHON_BLACK_FILE_NAME="${PYTHON_BLACK_CONFIG_FILE:-.python-black}"
 # shellcheck disable=SC2034  # Variable is referenced indirectly