diff --git a/README.md b/README.md
index e67bff9d..3b602da7 100644
--- a/README.md
+++ b/README.md
@@ -191,6 +191,7 @@ using the matched rule and runs it. Rules enabled by default are as follows:
 * `tsuru_login` – runs `tsuru login` if not authenticated or session expired;
 * `tsuru_not_command` – fixes wrong `tsuru` commands like `tsuru shell`;
 * `tmux` – fixes `tmux` commands;
+* `unknown_command` – fixes hadoop hdfs-style "unknown command" for example adds missing '-' to the command on `hdfs dfs ls`;
 * `whois` – fixes `whois` command.
 
 Enabled by default only on specific platforms:
diff --git a/tests/rules/test_unknown_command.py b/tests/rules/test_unknown_command.py
new file mode 100644
index 00000000..a31c9d9c
--- /dev/null
+++ b/tests/rules/test_unknown_command.py
@@ -0,0 +1,35 @@
+import pytest
+from thefuck.rules.unknown_command import match, get_new_command
+from tests.utils import Command
+
+
+@pytest.mark.parametrize('command', [
+    Command(script='./bin/hdfs dfs ls', stderr='ls: Unknown command\nDid you mean -ls?  This command begins with a dash.'),
+    Command(script='hdfs dfs ls',
+            stderr='ls: Unknown command\nDid you mean -ls?  This command begins with a dash.'),
+    Command(script='hdfs dfs ls /foo/bar', stderr='ls: Unknown command\nDid you mean -ls?  This command begins with a dash.')])
+def test_match(command):
+    assert match(command, None)
+
+
+@pytest.mark.parametrize('command', [
+    Command(script='./bin/hdfs dfs -ls', stderr=''),
+    Command(script='./bin/hdfs dfs -ls /foo/bar', stderr=''),  
+    Command(script='hdfs dfs -ls -R /foo/bar', stderr=''),  
+    Command()])
+def test_not_match(command):
+    assert not match(command, None)
+
+
+@pytest.mark.parametrize('command, new_command', [
+    (Command('hdfs dfs ls',
+        stderr='ls: Unknown command\nDid you mean -ls?  This command begins with a dash.'), ['hdfs dfs -ls']),
+    (Command('hdfs dfs rm /foo/bar',
+        stderr='rm: Unknown command\nDid you mean -rm?  This command begins with a dash.'), ['hdfs dfs -rm /foo/bar']),
+    (Command('./bin/hdfs dfs ls -R /foo/bar',
+        stderr='ls: Unknown command\nDid you mean -ls?  This command begins with a dash.'), ['./bin/hdfs dfs -ls -R /foo/bar']),
+    (Command('./bin/hdfs dfs -Dtest=fred ls -R /foo/bar',
+        stderr='ls: Unknown command\nDid you mean -ls?  This command begins with a dash.'), ['./bin/hdfs dfs -Dtest=fred -ls -R /foo/bar'])])
+def test_get_new_command(command, new_command):
+    assert get_new_command(command, None) == new_command
+
diff --git a/thefuck/rules/unknown_command.py b/thefuck/rules/unknown_command.py
new file mode 100644
index 00000000..d8632251
--- /dev/null
+++ b/thefuck/rules/unknown_command.py
@@ -0,0 +1,13 @@
+import re
+from thefuck.utils import (replace_command, get_all_matched_commands)
+
+def match(command, settings):
+    return (re.search(r"([^:]*): Unknown command.*", command.stderr) != None
+            and re.search(r"Did you mean ([^?]*)?", command.stderr) != None)
+
+
+def get_new_command(command, settings):
+    broken_cmd = re.findall(r"([^:]*): Unknown command.*", command.stderr)[0]
+    matched = re.findall(r"Did you mean ([^?]*)?", command.stderr)
+    return replace_command(command, broken_cmd, matched)
+