Japan's Left Priority Rule: Who Goes First at Uncontrolled Intersections?
· GaimenGo Team

One of the most misunderstood rules in Japan's driving test — the 左方優先 (Sahō Yūsen — Left Priority) rule explained clearly.
What Is the Left Priority Rule?
At many intersections in Japan — especially in residential areas — there are no traffic signals, no stop signs, and no priority road markings. Who goes first? The answer is Article 36 of Japan's Road Traffic Act (道路交通法第36条 — Dōro Kōtsū Hō Dai 36-jō): the vehicle coming from the LEFT has priority.
This is called 左方優先 (Sahō Yūsen — Left Priority).
When Does It Apply?
All three conditions must be met:
- The intersection has no traffic signals
- There is no priority road (優先道路 — Yūsen Dōro) marking or sign
- The intersecting roads are of equal width
If any of these conditions is not met, a different rule takes over.
The Priority Hierarchy
- Priority road (優先道路 — Yūsen Dōro) — the road with a centerline or priority sign always goes first
- Wider road — if no priority marking, the wider road has priority
- Left priority (左方優先 — Sahō Yūsen) — only when widths are equal and no signs apply
What About Stop Signs?
Here's a common exam trap: if both roads have stop signs (一時停止 — Ichiji Teishi), both cars must stop first, and then left priority applies. The stop signs create equal footing — and left priority then determines who proceeds first.
However, if only one road has a stop sign, that vehicle must yield to the other — regardless of which side it comes from.
Memory Tip
Think of it this way: in Japan, you drive on the left, you keep left, and at equal intersections, you yield to the left. Everything in Japanese traffic law leans left.
Key Exam Questions to Watch
- 'At an equal-width unsignalled intersection, the vehicle from the right must yield' → True
- 'Left priority applies even when one road has a stop sign and the other does not' → False
- 'When both roads have stop signs, left priority applies after both vehicles stop' → True
Reference: 道路交通法第36条 (Dōro Kōtsū Hō Dai 36-jō — Road Traffic Act Article 36), JAF Traffic Rules.