diff --git a/.gitmodules b/.gitmodules
index 16e7ed6..5a1a157 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -190,3 +190,6 @@
 [submodule "site-lisp/plantuml-mode"]
 	path = site-lisp/plantuml-mode
 	url = https://github.com/skuro/plantuml-mode.git
+[submodule "site-lisp/graphviz-dot-mode"]
+	path = site-lisp/graphviz-dot-mode
+	url = https://github.com/ppareit/graphviz-dot-mode.git
diff --git a/lisp/init-editorconfig.el b/lisp/init-editorconfig.el
index ce15141..d2a4604 100644
--- a/lisp/init-editorconfig.el
+++ b/lisp/init-editorconfig.el
@@ -26,7 +26,8 @@
 
 (with-eval-after-load 'editorconfig
   (add-to-list 'editorconfig-indentation-alist '(js-ts-mode js-indent-level))
-  (add-to-list 'editorconfig-indentation-alist '(plantuml-mode plantuml-indent-level)))
+  (add-to-list 'editorconfig-indentation-alist '(plantuml-mode plantuml-indent-level))
+  (add-to-list 'editorconfig-indentation-alist '(graphviz-dot-mode graphviz-dot-indent-width)))
 
 
 (provide 'init-editorconfig)
diff --git a/lisp/init-file.el b/lisp/init-file.el
index 622b643..8ff703f 100644
--- a/lisp/init-file.el
+++ b/lisp/init-file.el
@@ -56,6 +56,10 @@
 (add-to-list 'auto-mode-alist '("CMakeLists\\.txt\\'" . cmake-mode))
 (add-to-list 'auto-mode-alist '("\\.cmake\\'" . cmake-mode))
 
+(autoload 'graphviz-dot-mode "graphviz-dot-mode" "" t)
+(add-to-list 'auto-mode-alist '("\\.dot\\'" . graphviz-dot-mode))
+(add-to-list 'auto-mode-alist '("\\.gv\\'" . graphviz-dot-mode))
+
 ;; optimize performance of long-line files
 (setq-default bidi-display-reordering t)
 (setq bidi-inhibit-bpa t
diff --git a/lisp/init-org.el b/lisp/init-org.el
index 0ced56b..371d2cd 100644
--- a/lisp/init-org.el
+++ b/lisp/init-org.el
@@ -83,5 +83,9 @@
 (with-eval-after-load 'ob-plantuml
   (setq org-plantuml-exec-mode 'plantuml))
 
+(with-eval-after-load 'org-src
+  (defvar org-src-lang-modes)
+  (add-to-list 'org-src-lang-modes  '("dot" . graphviz-dot)))
+
 
 (provide 'init-org)
diff --git a/site-lisp/graphviz-dot-mode b/site-lisp/graphviz-dot-mode
new file mode 160000
index 0000000..8ff793b
--- /dev/null
+++ b/site-lisp/graphviz-dot-mode
@@ -0,0 +1 @@
+Subproject commit 8ff793b13707cb511875f56e167ff7f980a31136