Kanagawa's Tokaidai Sagami reached the National High School Baseball Championship final for the first time in 40 years after beating Narita of Chiba 11-7 on Friday.
Tokaidai Sagami, which is seeking its second championship since winning the tournament in 1970, will face Okinawa's Konan in Saturday's final at Koshien Stadium.
Konan beat Hotoku Gakuen of Hyogo 6-5 in the first semifinal, reaching the title game for the first time.
Tokaidai Sagami rapped out 19 hits against Narita, taking the lead in a four-run fifth behind Yutaro Someya's two-RBI triple.
Konan was down 5-0 after two innings as ace Yosuke Shimabukuro got off to a rocky start. But Konan kicked off its comeback with three runs in the top of the fifth before wresting the lead for good with a two-run seventh.
Shimabukuro pitched a complete game and had 12 strikeouts.