diff --git a/src/emu/debug/debugcpu.cpp b/src/emu/debug/debugcpu.cpp
index 957834ec831..ecd4996b320 100644
--- a/src/emu/debug/debugcpu.cpp
+++ b/src/emu/debug/debugcpu.cpp
@@ -3318,7 +3318,14 @@ void device_debug::tracer::update(offs_t pc)
 	// print the address
 	std::string buffer;
 	int logaddrchars = m_debug.logaddrchars();
-	buffer = string_format("%0*X: ", logaddrchars, pc);
+	if (m_debug.is_octal())
+	{
+		buffer = string_format("%0*o: ", logaddrchars*3/2, pc);
+	}
+	else
+	{
+		buffer = string_format("%0*X: ", logaddrchars, pc);
+	}
 
 	// print the disassembly
 	std::string dasm;
diff --git a/src/emu/debug/debugcpu.h b/src/emu/debug/debugcpu.h
index 5afb6fbceec..da97944d244 100644
--- a/src/emu/debug/debugcpu.h
+++ b/src/emu/debug/debugcpu.h
@@ -171,6 +171,7 @@ public:
 
 	// commonly-used pass-throughs
 	int logaddrchars() const { return (m_memory != nullptr && m_memory->has_space(AS_PROGRAM)) ? m_memory->space(AS_PROGRAM).logaddrchars() : 8; }
+	bool is_octal() const { return (m_memory != nullptr && m_memory->has_space(AS_PROGRAM)) ? m_memory->space(AS_PROGRAM).is_octal() : false; }
 	device_t& device() const { return m_device; }
 
 	// hooks used by the rest of the system