diff --git a/src/analyzer/protocol/dhcp/dhcp-options.pac b/src/analyzer/protocol/dhcp/dhcp-options.pac
index 0560f3cdc9..b572f297b3 100644
--- a/src/analyzer/protocol/dhcp/dhcp-options.pac
+++ b/src/analyzer/protocol/dhcp/dhcp-options.pac
@@ -627,7 +627,16 @@ refine flow DHCP_Flow += {
 		%{
 		auto client_id = make_intrusive<RecordVal>(zeek::BifType::Record::DHCP::ClientID);
 		client_id->Assign(0, val_mgr->Count(${v.client_id.hwtype}));
-		client_id->Assign(1, make_intrusive<StringVal>(fmt_mac(${v.client_id.hwaddr}.begin(), ${v.client_id.hwaddr}.length())));
+		IntrusivePtr<StringVal> sv;
+
+		if ( ${v.client_id.hwtype} == 0 )
+			sv = make_intrusive<StringVal>(${v.client_id.hwaddr}.length(),
+			                               (const char*)${v.client_id.hwaddr}.begin());
+		else
+			sv = make_intrusive<StringVal>(fmt_mac(${v.client_id.hwaddr}.begin(),
+			                               ${v.client_id.hwaddr}.length()));
+
+		client_id->Assign(1, std::move(sv));
 
 		${context.flow}->options->Assign(19, std::move(client_id));
 
diff --git a/testing/btest/Baseline/scripts.base.protocols.dhcp.hw-type0/out b/testing/btest/Baseline/scripts.base.protocols.dhcp.hw-type0/out
new file mode 100644
index 0000000000..041d527cdf
--- /dev/null
+++ b/testing/btest/Baseline/scripts.base.protocols.dhcp.hw-type0/out
@@ -0,0 +1 @@
+dhcp client_id option, [hwtype=0, hwaddr=cisco-cc00.0ac4.0000-Fa0/0]
diff --git a/testing/btest/Traces/dhcp/hw-type0.pcap b/testing/btest/Traces/dhcp/hw-type0.pcap
new file mode 100644
index 0000000000..c8f314f784
Binary files /dev/null and b/testing/btest/Traces/dhcp/hw-type0.pcap differ
diff --git a/testing/btest/scripts/base/protocols/dhcp/hw-type0.zeek b/testing/btest/scripts/base/protocols/dhcp/hw-type0.zeek
new file mode 100644
index 0000000000..2ac4cb8f6a
--- /dev/null
+++ b/testing/btest/scripts/base/protocols/dhcp/hw-type0.zeek
@@ -0,0 +1,16 @@
+# @TEST-EXEC: zeek -b -r $TRACES/dhcp/hw-type0.pcap %INPUT >out
+# @TEST-EXEC: btest-diff out
+
+const ports = { 67/udp, 68/udp };
+redef likely_server_ports += { 67/udp };
+
+event zeek_init() &priority=5
+	{
+	Analyzer::register_for_ports(Analyzer::ANALYZER_DHCP, ports);
+	}
+
+event dhcp_message(c: connection, is_orig: bool, msg: DHCP::Msg, options: DHCP::Options)
+	{
+	if ( options?$client_id )
+		print "dhcp client_id option", options$client_id;
+	}