diff --git a/core/tests/Drupal/Tests/ComposerIntegrationTest.php b/core/tests/Drupal/Tests/ComposerIntegrationTest.php
index 511fd52..266cbeb 100644
--- a/core/tests/Drupal/Tests/ComposerIntegrationTest.php
+++ b/core/tests/Drupal/Tests/ComposerIntegrationTest.php
@@ -2,6 +2,8 @@
 
 namespace Drupal\Tests;
 
+use Composer\Semver\Semver;
+
 /**
  * Tests Composer integration.
  *
@@ -10,6 +12,15 @@
 class ComposerIntegrationTest extends UnitTestCase {
 
   /**
+   * The minimum PHP version supported by Drupal.
+   *
+   * @see https://www.drupal.org/docs/8/system-requirements/web-server
+   *
+   * @todo Remove as part of https://www.drupal.org/node/2908079
+   */
+  const MIN_PHP_VERSION = '5.5.9';
+
+  /**
    * Gets human-readable JSON error messages.
    *
    * @return string[]
@@ -170,6 +181,29 @@ public function testAllModulesReplaced() {
     }
   }
 
+  /**
+   * Tests package requirements for the minimum supported PHP version by Drupal.
+   *
+   * @todo This can be removed when DrupalCI supports dependency regression
+   *   testing in https://www.drupal.org/node/2874198
+   */
+  public function testMinPHPVersion() {
+    // Check for lockfile in the application root. If the lockfile does not
+    // exist, then skip this test.
+    $lockfile = $this->root . '/composer.lock';
+    if (!file_exists($lockfile)) {
+      $this->markTestSkipped('/composer.lock is not available.');
+    }
+
+    $lock = json_decode(file_get_contents($lockfile), TRUE);
+
+    foreach ($lock['packages'] as $package) {
+      if (isset($package['require']['php'])) {
+        $this->assertTrue(Semver::satisfies(static::MIN_PHP_VERSION, $package['require']['php']), $package['name'] . ' has a PHP dependency requirement of "' . $package['require']['php'] . '"');
+      }
+    }
+  }
+
   // @codingStandardsIgnoreStart
   /**
    * The following method is copied from \Composer\Package\Locker.