diff --git a/builder/qemu/builder.go b/builder/qemu/builder.go
index 0ee680f56..10c821b7e 100644
--- a/builder/qemu/builder.go
+++ b/builder/qemu/builder.go
@@ -146,8 +146,10 @@ type Config struct {
 	// one of the other listed interfaces. Using the `scsi` interface under
 	// these circumstances will cause the build to fail.
 	DiskInterface string `mapstructure:"disk_interface" required:"false"`
-	// The size, in megabytes, of the hard disk to create
-	// for the VM. By default, this is 40960 (40 GB).
+	// The size in bytes, suffixes of the first letter of common byte types
+	// like "k" or "K", "M" for megabytes, G for gigabytes, T for terabytes.
+	// Will create the of the hard disk of the VM. By default, this is
+	// `40960M` (40 GB).
 	DiskSize string `mapstructure:"disk_size" required:"false"`
 	// The cache mode to use for disk. Allowed values include any of
 	// `writethrough`, `writeback`, `none`, `unsafe` or `directsync`. By
diff --git a/website/source/partials/builder/qemu/_Config-not-required.html.md b/website/source/partials/builder/qemu/_Config-not-required.html.md
index 07ac4256a..723c53276 100644
--- a/website/source/partials/builder/qemu/_Config-not-required.html.md
+++ b/website/source/partials/builder/qemu/_Config-not-required.html.md
@@ -47,8 +47,10 @@
     one of the other listed interfaces. Using the `scsi` interface under
     these circumstances will cause the build to fail.
     
--   `disk_size` (uint) - The size, in megabytes, of the hard disk to create
-    for the VM. By default, this is 40960 (40 GB).
+-   `disk_size` (string) - The size in bytes, suffixes of the first letter of common byte types
+    like "k" or "K", "M" for megabytes, G for gigabytes, T for terabytes.
+    Will create the of the hard disk of the VM. By default, this is
+    `40960M` (40 GB).
     
 -   `disk_cache` (string) - The cache mode to use for disk. Allowed values include any of
     `writethrough`, `writeback`, `none`, `unsafe` or `directsync`. By