diff --git a/Configurations.md b/Configurations.md
index 6ba78e714e0..e584457a2e1 100644
--- a/Configurations.md
+++ b/Configurations.md
@@ -519,14 +519,6 @@ fn main() {
 }
 ```
 
-## `disable_all_formatting`
-
-Don't reformat anything
-
-- **Default value**: `false`
-- **Possible values**: `true`, `false`
-- **Stable**: No (tracking issue: [#3388](https://github.com/rust-lang/rustfmt/issues/3388))
-
 ## `edition`
 
 Specifies which edition is used by the parser.
diff --git a/rustfmt-core/rustfmt-bin/src/bin/main.rs b/rustfmt-core/rustfmt-bin/src/bin/main.rs
index 512fd311107..49d45e984f5 100644
--- a/rustfmt-core/rustfmt-bin/src/bin/main.rs
+++ b/rustfmt-core/rustfmt-bin/src/bin/main.rs
@@ -567,35 +567,6 @@ mod test {
         let _ = env_logger::builder().is_test(true).try_init();
     }
 
-    #[test]
-    fn stdin_disable_all_formatting_test() {
-        init_log();
-        match option_env!("CFG_RELEASE_CHANNEL") {
-            None | Some("nightly") => {}
-            // These tests require nightly.
-            _ => return,
-        }
-        let input = "fn main() { println!(\"This should not be formatted.\"); }";
-        let mut child = Command::new(rustfmt())
-            .stdin(Stdio::piped())
-            .stdout(Stdio::piped())
-            .arg("--config-path=./tests/config/disable_all_formatting.toml")
-            .spawn()
-            .expect("failed to execute child");
-
-        {
-            let stdin = child.stdin.as_mut().expect("failed to get stdin");
-            stdin
-                .write_all(input.as_bytes())
-                .expect("failed to write stdin");
-        }
-
-        let output = child.wait_with_output().expect("failed to wait on child");
-        assert!(output.status.success());
-        assert!(output.stderr.is_empty());
-        assert_eq!(input, String::from_utf8(output.stdout).unwrap());
-    }
-
     #[test]
     fn format_lines_errors_are_reported() {
         init_log();
diff --git a/rustfmt-core/rustfmt-bin/tests/config/disable_all_formatting.toml b/rustfmt-core/rustfmt-bin/tests/config/disable_all_formatting.toml
deleted file mode 100644
index c7ad93bafe3..00000000000
--- a/rustfmt-core/rustfmt-bin/tests/config/disable_all_formatting.toml
+++ /dev/null
@@ -1 +0,0 @@
-disable_all_formatting = true
diff --git a/rustfmt-core/rustfmt-lib/src/config.rs b/rustfmt-core/rustfmt-lib/src/config.rs
index 6b1c73ee4c1..27ee1881397 100644
--- a/rustfmt-core/rustfmt-lib/src/config.rs
+++ b/rustfmt-core/rustfmt-lib/src/config.rs
@@ -144,7 +144,6 @@ create_config! {
         "Require a specific version of rustfmt";
     unstable_features: bool, false, false,
             "Enables unstable features. Only available on nightly channel";
-    disable_all_formatting: bool, false, false, "Don't reformat anything";
     hide_parse_errors: bool, false, false, "Hide errors from the parser";
     error_on_line_overflow: bool, false, false, "Error if unable to get all lines within max_width";
     error_on_unformatted: bool, false, false,
@@ -572,7 +571,6 @@ condense_wildcard_suffixes = false
 color = "Auto"
 required_version = "{}"
 unstable_features = false
-disable_all_formatting = false
 hide_parse_errors = false
 error_on_line_overflow = false
 error_on_unformatted = false
diff --git a/rustfmt-core/rustfmt-lib/src/formatting.rs b/rustfmt-core/rustfmt-lib/src/formatting.rs
index a3766a99f43..1f92b005e66 100644
--- a/rustfmt-core/rustfmt-lib/src/formatting.rs
+++ b/rustfmt-core/rustfmt-lib/src/formatting.rs
@@ -29,16 +29,6 @@ impl<'b, T: Write + 'b> Session<'b, T> {
         }
 
         rustc_ast::with_globals(self.config.edition().into(), || {
-            if self.config.disable_all_formatting() {
-                // When the input is from stdin, echo back the input.
-                if let Input::Text(ref buf) = input {
-                    if let Err(e) = io::stdout().write_all(buf.as_bytes()) {
-                        return Err(From::from(e));
-                    }
-                }
-                return Ok(FormatReport::new());
-            }
-
             let config = &self.config.clone();
             let format_result = format_project(input, config, self);
 
diff --git a/rustfmt-core/rustfmt-lib/tests/source/configs/disable_all_formatting/false.rs b/rustfmt-core/rustfmt-lib/tests/source/configs/disable_all_formatting/false.rs
deleted file mode 100644
index 834ca7a3c89..00000000000
--- a/rustfmt-core/rustfmt-lib/tests/source/configs/disable_all_formatting/false.rs
+++ /dev/null
@@ -1,6 +0,0 @@
-// rustfmt-disable_all_formatting: false
-// Disable all formatting
-
-fn main() {
-    if lorem{println!("ipsum!");}else{println!("dolor!");}
-}
diff --git a/rustfmt-core/rustfmt-lib/tests/source/configs/disable_all_formatting/true.rs b/rustfmt-core/rustfmt-lib/tests/source/configs/disable_all_formatting/true.rs
deleted file mode 100644
index 56955bf384d..00000000000
--- a/rustfmt-core/rustfmt-lib/tests/source/configs/disable_all_formatting/true.rs
+++ /dev/null
@@ -1,6 +0,0 @@
-// rustfmt-disable_all_formatting: true
-// Disable all formatting
-
-fn main() {
-    iflorem{println!("ipsum!");}else{println!("dolor!");}
-}
diff --git a/rustfmt-core/rustfmt-lib/tests/target/configs/disable_all_formatting/false.rs b/rustfmt-core/rustfmt-lib/tests/target/configs/disable_all_formatting/false.rs
deleted file mode 100644
index 1a0477ddb39..00000000000
--- a/rustfmt-core/rustfmt-lib/tests/target/configs/disable_all_formatting/false.rs
+++ /dev/null
@@ -1,10 +0,0 @@
-// rustfmt-disable_all_formatting: false
-// Disable all formatting
-
-fn main() {
-    if lorem {
-        println!("ipsum!");
-    } else {
-        println!("dolor!");
-    }
-}
diff --git a/rustfmt-core/rustfmt-lib/tests/target/configs/disable_all_formatting/true.rs b/rustfmt-core/rustfmt-lib/tests/target/configs/disable_all_formatting/true.rs
deleted file mode 100644
index 736ccf56942..00000000000
--- a/rustfmt-core/rustfmt-lib/tests/target/configs/disable_all_formatting/true.rs
+++ /dev/null
@@ -1,6 +0,0 @@
-// rustfmt-disable_all_formatting: true
-// Disable all formatting
-
-fn main() {
-    if lorem{println!("ipsum!");}else{println!("dolor!");}
-}