diff --git a/AxonIvyPortal/portal-components/src/com/axonivy/portal/components/bean/PortalComponentAvatarBean.java b/AxonIvyPortal/portal-components/src/com/axonivy/portal/components/bean/PortalComponentAvatarBean.java
index 7688d8f8dae..a2e18c6bcac 100644
--- a/AxonIvyPortal/portal-components/src/com/axonivy/portal/components/bean/PortalComponentAvatarBean.java
+++ b/AxonIvyPortal/portal-components/src/com/axonivy/portal/components/bean/PortalComponentAvatarBean.java
@@ -1,9 +1,12 @@
 package com.axonivy.portal.components.bean;
 
 import java.io.Serializable;
+import java.util.Optional;
 
 import javax.faces.bean.ManagedBean;
 
+import org.apache.commons.lang3.BooleanUtils;
+
 import com.axonivy.portal.components.dto.RoleDTO;
 import com.axonivy.portal.components.dto.SecurityMemberDTO;
 import com.axonivy.portal.components.dto.UserDTO;
@@ -27,11 +30,16 @@ public String getNameInitials(String displayName) {
     return SecurityMemberUtils.getNameInitials(displayName);
   }
 
-  public String getEmailAddress(ISecurityMember securityMember) {
+  public String getEmailAddress(ISecurityMember securityMember,
+      boolean useLowercaseEmail) {
     if (securityMember == null || !securityMember.isUser()) {
       return "";
     }
-    return ((IUser) securityMember).getEMailAddress();
+
+    String email = ((IUser) securityMember).getEMailAddress();
+    return BooleanUtils.isTrue(useLowercaseEmail)
+        ? Optional.ofNullable(email).map(String::toLowerCase).orElse(email)
+        : email;
   }
 
   public String getEmailAddress(SecurityMemberDTO securityMember) {
diff --git a/AxonIvyPortal/portal-components/webContent/resources/components/avatar.xhtml b/AxonIvyPortal/portal-components/webContent/resources/components/avatar.xhtml
index 90c977f87cc..d3c7619621e 100644
--- a/AxonIvyPortal/portal-components/webContent/resources/components/avatar.xhtml
+++ b/AxonIvyPortal/portal-components/webContent/resources/components/avatar.xhtml
@@ -6,13 +6,14 @@
   <cc:attribute name="securityMember" required="true" />
   <cc:attribute name="id" />
   <cc:attribute name="renderedAvatar" default="#{portalComponentAvatarBean.getPortalShowAvatarSettingOrDefault(true)}" />
+  <cc:attribute name="useLowercaseEmail" default="true" shortDescription="Convert the email address to lowercase before looking up the avatar." />
 </cc:interface>
 
 <cc:implementation>
   <h:outputStylesheet library="css" name="portal-components.css" />
 
   <p:avatar id="#{cc.attrs.id}" rendered="#{cc.attrs.renderedAvatar}"
-    gravatar="#{portalComponentAvatarBean.getEmailAddress(cc.attrs.securityMember)}" gravatarConfig="d=blank"
+    gravatar="#{portalComponentAvatarBean.getEmailAddress(cc.attrs.securityMember, cc.attrs.useLowercaseEmail)}" gravatarConfig="d=blank"
     label="#{portalComponentAvatarBean.getNameInitials(cc.attrs.securityMember.getDisplayName())}" styleClass="gravatar" shape="circle" />
 </cc:implementation>
 </html>
\ No newline at end of file