diff --git a/src/__phutil_library_map__.php b/src/__phutil_library_map__.php
--- a/src/__phutil_library_map__.php
+++ b/src/__phutil_library_map__.php
@@ -607,6 +607,7 @@
     'DiffusionLowLevelGitRefQuery' => 'applications/diffusion/query/lowlevel/DiffusionLowLevelGitRefQuery.php',
     'DiffusionLowLevelMercurialBranchesQuery' => 'applications/diffusion/query/lowlevel/DiffusionLowLevelMercurialBranchesQuery.php',
     'DiffusionLowLevelMercurialPathsQuery' => 'applications/diffusion/query/lowlevel/DiffusionLowLevelMercurialPathsQuery.php',
+    'DiffusionLowLevelMercurialPathsQueryTests' => 'applications/diffusion/query/lowlevel/__tests__/DiffusionLowLevelMercurialPathsQueryTests.php',
     'DiffusionLowLevelParentsQuery' => 'applications/diffusion/query/lowlevel/DiffusionLowLevelParentsQuery.php',
     'DiffusionLowLevelQuery' => 'applications/diffusion/query/lowlevel/DiffusionLowLevelQuery.php',
     'DiffusionLowLevelResolveRefsQuery' => 'applications/diffusion/query/lowlevel/DiffusionLowLevelResolveRefsQuery.php',
@@ -4340,6 +4341,7 @@
     'DiffusionLowLevelGitRefQuery' => 'DiffusionLowLevelQuery',
     'DiffusionLowLevelMercurialBranchesQuery' => 'DiffusionLowLevelQuery',
     'DiffusionLowLevelMercurialPathsQuery' => 'DiffusionLowLevelQuery',
+    'DiffusionLowLevelMercurialPathsQueryTests' => 'PhabricatorTestCase',
     'DiffusionLowLevelParentsQuery' => 'DiffusionLowLevelQuery',
     'DiffusionLowLevelQuery' => 'Phobject',
     'DiffusionLowLevelResolveRefsQuery' => 'DiffusionLowLevelQuery',
diff --git a/src/applications/diffusion/query/lowlevel/DiffusionLowLevelMercurialPathsQuery.php b/src/applications/diffusion/query/lowlevel/DiffusionLowLevelMercurialPathsQuery.php
--- a/src/applications/diffusion/query/lowlevel/DiffusionLowLevelMercurialPathsQuery.php
+++ b/src/applications/diffusion/query/lowlevel/DiffusionLowLevelMercurialPathsQuery.php
@@ -24,13 +24,41 @@
     $path = $this->path;
     $commit = $this->commit;
 
+    $hg_version = PhabricatorRepositoryVersion::getMercurialVersion();
+    $hg_paths_command = $this->getMercurialPathsCommand($hg_version);
+
     $match_against = trim($path, '/');
     $prefix = trim('./'.$match_against, '/');
     list($entire_manifest) = $repository->execxLocalCommand(
-      'locate --print0 --rev %s -I %s',
+      $hg_paths_command,
       hgsprintf('%s', $commit),
       $prefix);
     return explode("\0", $entire_manifest);
   }
 
+  /** The `locate` command is deprecated as of Mercurial 3.2, to be
+   * replaced with `files` command, which supports most of the same
+   * arguments. This returns the correct command to use based on the
+   * version of Mercurial in use. The returned value is expected to
+   * be used directly by PhabricatorRepository::execxLocalCommand with
+   * two arguments.
+   *
+   * @param string  $hg_version - The current version of mercurial
+   *   which can be retrieved by calling:
+   *   PhabricatorRepositoryVersion::getMercurialVersion()
+   *
+   * @return string  The mercurial command & arguments to be used in
+   *   order to retrieve paths of tracked files. The returned string
+   *   is formatted with two '%s' to supply argument values. The first
+   *   is the revision argument ('--rev') and the second is the include
+   *   file pattern ('-I').
+   */
+  public function getMercurialPathsCommand($hg_version) {
+    $min_version_for_files = '3.2';
+    if (version_compare($hg_version, $min_version_for_files, '>=')) {
+      return 'files --print0 --rev %s -I %s';
+    }
+    return 'locate --print0 --rev %s -I %s';
+  }
+
 }
diff --git a/src/applications/diffusion/query/lowlevel/__tests__/DiffusionLowLevelMercurialPathsQueryTests.php b/src/applications/diffusion/query/lowlevel/__tests__/DiffusionLowLevelMercurialPathsQueryTests.php
new file mode 100644
--- /dev/null
+++ b/src/applications/diffusion/query/lowlevel/__tests__/DiffusionLowLevelMercurialPathsQueryTests.php
@@ -0,0 +1,31 @@
+<?php
+
+final class DiffusionLowLevelMercurialPathsQueryTests
+  extends PhabricatorTestCase {
+
+  public function testCommandByVersion() {
+    $cases = array(
+      array(
+        'name' => pht('Versions which should use `locate`'),
+        'versions' => array('2.6.2', '2.9', '3.1'),
+        'match' => 'locate',
+      ),
+
+      array(
+        'name' => pht('Versions which should use `files`'),
+        'versions' => array('3.2', '3.3', '3.5.2'),
+        'match' => 'files',
+      ),
+    );
+
+    foreach ($cases as $case) {
+      $query = new DiffusionLowLevelMercurialPathsQuery();
+      foreach ($case['versions'] as $version) {
+        $actual = $query->getMercurialPathsCommand($version);
+        $expect = preg_match('/^'.$case['match'].'/', $actual);
+        $this->assertEqual($expect, 1, $case['name']);
+      }
+    }
+  }
+
+}