diff --git a/util/bot/DEPS b/util/bot/DEPS
index ac923541..ab6b94e9 100644
--- a/util/bot/DEPS
+++ b/util/bot/DEPS
@@ -18,6 +18,7 @@ vars = {
   'checkout_clang': False,
   'checkout_fuzzer': False,
   'checkout_sde': False,
+  'checkout_nasm': False,
 }
 
 deps = {
@@ -138,7 +139,7 @@ hooks = [
   {
     'name': 'yasm_win32',
     'pattern': '.',
-    'condition': 'host_os == "win"',
+    'condition': 'host_os == "win" and not checkout_nasm',
     'action': [ 'download_from_google_storage',
                 '--no_resume',
                 '--platform=win32',
@@ -147,6 +148,18 @@ hooks = [
                 '-s', 'boringssl/util/bot/yasm-win32.exe.sha1',
     ],
   },
+  {
+    'name': 'nasm_win32',
+    'pattern': '.',
+    'condition': 'host_os == "win" and checkout_nasm',
+    'action': [ 'download_from_google_storage',
+                '--no_resume',
+                '--platform=win32',
+                '--no_auth',
+                '--bucket', 'chromium-tools',
+                '-s', 'boringssl/util/bot/nasm-win32.exe.sha1',
+    ],
+  },
   {
     'name': 'win_toolchain',
     'pattern': '.',
diff --git a/util/bot/UPDATING b/util/bot/UPDATING
index f5a831b4..b358f510 100644
--- a/util/bot/UPDATING
+++ b/util/bot/UPDATING
@@ -41,6 +41,16 @@ cmake-win32.zip: Update to the latest prebuilt release of CMake, found at
 
     The current revision is cmake-3.10.1-win32-x86.zip.
 
+nasm-win32.exe: Update to the appropriate release of NASM, found at
+    https://www.nasm.us/. Use the same version as Chromium, found at
+    https://chromium.googlesource.com/chromium/src/+/master/third_party/nasm/README.chromium
+    Extract nasm.exe from the download named nasm-VERSION-win32.zip.
+
+    The current revision is nasm-2.13.03-win32.zip.
+
+    TODO(davidben): The Chromium link currently does not work. It will get
+    filled in in the future. See https://crbug.com/766721.
+
 perl-win32.zip: Update to the latest 32-bit prebuilt "Portable" edition of
     Strawberry Perl, found at http://strawberryperl.com/releases.html. The
     download will be named strawberry-perl-VERSION-32bit-portable.zip.
diff --git a/util/bot/nasm-win32.exe.sha1 b/util/bot/nasm-win32.exe.sha1
new file mode 100644
index 00000000..009bb3c7
--- /dev/null
+++ b/util/bot/nasm-win32.exe.sha1
@@ -0,0 +1 @@
+41438548185ed402ad713b4d5b90187737585d4a
\ No newline at end of file