Miura, affectionately known as "King Kazu", struck in the 52nd minute to put Fukushima 5-0 ahead, capping a trademark run into the box by meeting a teammate's cutback with a first-time finish at 59 years and 149 days.
The goal sparked celebrations among teammates on the pitch and the bench before the veteran forward was substituted three minutes later.
It was Miura's first competitive goal since November 2022, when he scored for Suzuka PG, now Atletico Suzuka, in a Japan Football League defeat by FC Osaka.
The former Japan international is preparing for a remarkable 42nd season as a professional after extending his loan spell with third-tier Fukushima United until June 2027.
Miura joined the club from Yokohama FC in December and will remain with Fukushima after making six appearances during a shortened 2026 campaign.
With Japan's professional leagues set to switch from a spring-to-autumn schedule to an autumn-to-spring calendar, Miura will enter his 60s still playing professionally, adding another chapter to one of soccer's most enduring careers.