No, visa-free for up to 90 days. Hong Kong SAR passport holders can visit Japan visa-free for short-term stays of up to 90 days. Japan also lists BNO passport holders with right of residence in Hong Kong under the Hong Kong note, but travellers should verify the exact travel document before booking.
For guidance only — visa rules change with little notice. Always confirm directly with the destination's embassy or foreign ministry before booking non-refundable travel. Information here applies to ordinary (non-diplomatic) passports unless noted.