diff --git a/instances.tf b/instances.tf
index 8131459..04b2864 100644
--- a/instances.tf
+++ b/instances.tf
@@ -19,7 +19,7 @@ data "aws_ami" "ubuntu_linux" {
   tags = merge(
     var.tags,
     {
-      ApprovedAMI = var.tagApprovedAMIvalue
+      ApprovedAMI = var.tag_approved_ami_value
     },
   )
 }
diff --git a/variables.tf b/variables.tf
index a17a0ae..f92dac4 100644
--- a/variables.tf
+++ b/variables.tf
@@ -96,7 +96,7 @@ variable "tags" {
   default     = {}
 }
 
-variable "tagApprovedAMIvalue" {
+variable "tag_approved_ami_value" {
   type        = string
   description = "Set the specific tag ApprovedAMI ('true' | 'false') that identifies aws-config compliant AMIs"
   default     = "false"