diff --git a/README.md b/README.md
index a955a4b..8c92845 100644
--- a/README.md
+++ b/README.md
@@ -75,6 +75,10 @@ curl ... | sudo bash -s -- --unattended --dns1 9.9.9.9 --dns2 149.112.112.112
 ### Set Admin Password
 
 ```bash
+# Pi-hole v6+
+pihole setpassword
+
+# Pi-hole v5 (legacy)
 pihole -a -p
 ```
 
@@ -185,7 +189,7 @@ journalctl -u pihole-FTL -f        # Systemd journal
 ### Reset admin password
 
 ```bash
-pihole -a -p
+pihole setpassword
 ```
 
 ## Uninstall
diff --git a/install.sh b/install.sh
index cfa3c08..74318f1 100644
--- a/install.sh
+++ b/install.sh
@@ -498,12 +498,19 @@ configure_firewall() {
 set_admin_password() {
     if [ -n "$ADMIN_PASSWORD" ]; then
         log "Setting admin password..."
-        pihole -a -p "$ADMIN_PASSWORD"
-        success "Admin password set"
+        # Pi-hole v6 uses 'setpassword' instead of '-a -p'
+        if pihole setpassword "$ADMIN_PASSWORD" 2>/dev/null; then
+            success "Admin password set"
+        elif pihole -a -p "$ADMIN_PASSWORD" 2>/dev/null; then
+            success "Admin password set (legacy)"
+        else
+            warn "Could not set password automatically"
+        fi
     elif [ "$UNATTENDED" != true ]; then
         echo ""
         echo "Set your Pi-hole admin password:"
-        pihole -a -p
+        # Try v6 syntax first, fallback to legacy
+        pihole setpassword 2>/dev/null || pihole -a -p
     fi
 }
 
@@ -581,7 +588,7 @@ case "${1:-help}" in
         echo "Backup created: $backup_dir/pihole_backup_$timestamp.tar.gz"
         ;;
     password)
-        pihole -a -p
+        pihole setpassword 2>/dev/null || pihole -a -p
         ;;
     *)
         echo "Pi-hole Management Helper"