diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2c80ecd..1eb39aa 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,8 @@ Record of the modification in project development.
 
 ### Added
 ### Changed
+- [Issue 5 : OVERWRITEINSTALL confirmation is missing](https://github.com/suikan4github/kaiten-yaki/issues/5)
+
 ### Deprecated
 ### Removed
 ### Fixed
diff --git a/script/lib.sh b/script/lib.sh
index 7c874a6..d68bf77 100644
--- a/script/lib.sh
+++ b/script/lib.sh
@@ -70,9 +70,9 @@ function confirmation(){
 		return 1 # with error status
 	fi	# if YES
 
-	# For sure ask to be sure to erase. 
+	# For sure ask to erase. 
 	if [ "${ERASEALL}" -ne 0 ] ; then
-		echo "Are you sure you want to erase entire ${DEV}? [Y/N]"
+		echo "Are you sure you want to erase entire \"${DEV}\"? [Y/N]"
 		read -r YESNO
 		if [ "${YESNO}" != "Y" ] && [ "${YESNO}" != "y" ] ; then
 			cat <<-HEREDOC 
@@ -84,6 +84,20 @@ function confirmation(){
 		fi	# if YES
 	fi	# if erase all
 
+	# For sure ask to overwrite. 
+	if [ "${OVERWRITEINSTALL}" -ne 0 ] ; then
+		echo "Are you sure you want to overwrite \"${LVROOTNAME}\" in \"${VGNAME}\"? [Y/N]"
+		read -r YESNO
+		if [ "${YESNO}" != "Y" ] && [ "${YESNO}" != "y" ] ; then
+			cat <<-HEREDOC 
+		...Check your config.sh. The variable OVERWRITEINSTALL is ${OVERWRITEINSTALL}.
+
+		...Installation process terminated..
+		HEREDOC
+		return 1 # with error status
+		fi	# if YES
+	fi	# if overwrite
+
 	# ----- Set Passphrase -----
 	# Input passphrase
 	echo ""