(D)：Difending Champion
| Date | Championships | Course | Venue | Champion | |
| 4/21 – 4/24 | Asia Golf Circuit Dunlop Open Golf Championship | Ibaraki Golf Club East Course | IBARAKI | Masashi Ozaki | |
| 6/7 – 6/9 | 30th 1988 Japan Women’s Amateur Golf Championship | Kashiwa Golf Club | CHIBA | Michiko Hattori | |
| 7/5 – 7/8 | 73rd 1988 Japan Amateur Golf Championship | Rokkokokusai Golf Club East/Center Course | HYOGO | Ryoken Kawagishi | |
| 7/14 – 7/17 |  |
21st 1988 Japan Women’s Open Golf Championship | Dazaifu Golf Club | FUKUOKA | Fukumi Tani |
| 8/9 – 8/10 | 25th 1988 Japan Women’s Collegiate Golf Championship | ABC Golf Club | HYOGO | Kaori Harada | |
| 8/10 – 8/12 | 1988 Japan Junior Golf Championship High School Boys | Kasumigaseki Country Club West Course | SAITAMA | Kazuyoshi Yonekura | |
| 8/11 – 8/12 | 1988 Japan Junior Golf Championship Middle School Boys | Kasumigaseki Country Club West Course | SAITAMA | Tomoyuki Yamaguchi | |
| 8/11 – 8/12 | 1988 Japan Junior Golf Championship Girls | Kasumigaseki Country Club West Course | SAITAMA | Yukiyo Haga | |
| 8/22 – 8/23 | 42nd 1988 Japan Collegiate Golf Championship | Takanodai Country Club | CHIBA | Ryoken Kawagishi | |
| 10/6 – 10/9 | |
53rd 1988 Japan Open Golf Championship | Tokyo Golf Club | SAITAMA | Masashi Ozaki |
| 10/12 – 10/13 | 10th 1988 Japan Senior Golf Championship | Kasugai Country Club East Course | AICHI | Kinji Ando | |