diff --git a/xyz/openbmc_project/Network/MACAddress.interface.yaml b/xyz/openbmc_project/Network/MACAddress.interface.yaml
index df092f2..5c9daa0 100644
--- a/xyz/openbmc_project/Network/MACAddress.interface.yaml
+++ b/xyz/openbmc_project/Network/MACAddress.interface.yaml
@@ -5,7 +5,9 @@
     - name: MACAddress
       type: string
       description: >
-          MAC address of the ethernet interface.
+          MAC address of the ethernet interface in six groups of
+          two hexadecimal digits separated by colons.
+          Example: 01:23:45:67:89:AB
       errors:
         - xyz.openbmc_project.Common.Error.InvalidArgument
         - xyz.openbmc_project.Common.Error.InternalFailure