diff --git a/autoload/brightest.vim b/autoload/brightest.vim
index c026ae8..3c923a3 100644
--- a/autoload/brightest.vim
+++ b/autoload/brightest.vim
@@ -224,6 +224,9 @@ function! brightest#define_cursorline_highlight_group(group)
 endfunction
 
 
+let g:brightest#enable_insert_mode = get(g:, "brightest#enable_insert_mode", 0)
+
+
 function! s:is_enable()
 	return get(g:, "brightest_enable", 1) && get(b:, "brightest_enable", 1)
 endfunction
@@ -240,6 +243,7 @@ function! brightest#on_CursorHold()
 	endif
 endfunction
 
+
 let g:brightest#enable_clear_highlight_on_CursorMoved = get(g:, "brightest#enable_clear_highlight_on_CursorMoved", 1)
 function! brightest#on_CursorMoved()
 	if s:is_enable_on_cursorhold() && g:brightest#enable_clear_highlight_on_CursorMoved
@@ -251,5 +255,3 @@ function! brightest#on_CursorMoved()
 endfunction
 
 
-let &cpo = s:save_cpo
-unlet s:save_cpo
diff --git a/doc/brightest.jax b/doc/brightest.jax
index 3965e66..91b8bab 100644
--- a/doc/brightest.jax
+++ b/doc/brightest.jax
@@ -171,6 +171,13 @@ Default: >
 	let g:brightest#enable_clear_highlight_on_CursorMoved = 1
 <
 
+g:brightest#enable_insert_mode		*g:brightest#enable_insert_mode*
+	0 以外が設定されている場合に |Insert-mode| でも単語がハイライトされる
+	ようになります。
+Default: >
+	let g:brightest#enable_insert_mode = 0
+<
+
 ==============================================================================
 ハイライトグループ				*brightest-highlight_group*
 
diff --git a/plugin/brightest.vim b/plugin/brightest.vim
index 06298e1..aa6fe93 100644
--- a/plugin/brightest.vim
+++ b/plugin/brightest.vim
@@ -42,13 +42,29 @@ function! s:highlight()
 	endif
 endfunction
 
+
 augroup brightest
 	autocmd!
 " 	autocmd CursorMoved * call s:highlight()
 	autocmd CursorMoved * call brightest#on_CursorMoved()
 	autocmd CursorHold  * call brightest#on_CursorHold()
-	autocmd BufLeave,WinLeave,InsertEnter * call brightest#hl_clear()
+	autocmd BufLeave,WinLeave * call brightest#hl_clear()
 	autocmd ColorScheme * call s:init_hl()
+
+	autocmd CursorMovedI *
+\		if g:brightest#enable_insert_mode
+
+
+\|			call brightest#on_CursorMoved()
+\|		endif
+	autocmd CursorHoldI *
+\		if g:brightest#enable_insert_mode
+\|			call brightest#on_CursorHold()
+\|		endif
+	autocmd InsertEnter *
+\		if g:brightest#enable_insert_mode == 0
+\|			call brightest#hl_clear()
+\|		endif
 augroup END