diff --git a/doh-client/ietf.go b/doh-client/ietf.go
index 6ba7a1a..bc4e625 100644
--- a/doh-client/ietf.go
+++ b/doh-client/ietf.go
@@ -75,7 +75,7 @@ func (c *Client) generateRequestIETF(w dns.ResponseWriter, r *dns.Msg, isTCP boo
 		opt.Hdr.Rrtype = dns.TypeOPT
 		opt.SetUDPSize(dns.DefaultMsgSize)
 		opt.SetDo(false)
-		r.Extra = append(r.Extra, opt)
+		r.Extra = append([]dns.RR{opt}, r.Extra...)
 	} else {
 		udpSize = opt.UDPSize()
 	}
diff --git a/doh-server/ietf.go b/doh-server/ietf.go
index 60b43e4..869e5cb 100644
--- a/doh-server/ietf.go
+++ b/doh-server/ietf.go
@@ -95,7 +95,7 @@ func (s *Server) parseRequestIETF(w http.ResponseWriter, r *http.Request) *DNSRe
 		opt.Hdr.Rrtype = dns.TypeOPT
 		opt.SetUDPSize(dns.DefaultMsgSize)
 		opt.SetDo(false)
-		msg.Extra = append(msg.Extra, opt)
+		msg.Extra = append([]dns.RR{opt}, msg.Extra...)
 	}
 	var edns0Subnet *dns.EDNS0_SUBNET
 	for _, option := range opt.Option {