Gekiharo (ゲキハロ) is the name used for collaborative theater works between Japanese theater group Gekipro and Hello! Project. Fifteen Gekiharo stage plays were performed between 2006 and 2013. Gekiharo plays were retired with the creation of the Hello! Project exclusive acting club, Engeki Joshibu.
- From Berryz Koubou
- From ℃-ute
- From S/mileage
- From Morning Musume
- From Melon Kinenbi
- From Hello! Project
- From Hello Pro Egg
- From Up-Front Egg
-  Edo Kara Chakushin!? ~Timeslip to Kengai!~
-  Neruko wa ℃-ute
-  Reverse! ~ Watashi no Karada Doko Desu ka?
-  Keitai Shosetsuka
-  Berryz Koubou VS Berryz Koubou
-  Atarumo Hakke!?
-  Thank You Very Berry
-  Obaachanchi no Curry Rice ~Smile Recipe~
-  Sanokuen Shoujo
-  Taishou Roman Haikara Tantei Aoi Ruby Satsujinjiken
-  Sengoku Jieitai
-  CAT'S♥EYE
-  Sakura no Hanataba (Special)
-  Gogakuyuu (Collaboration)
-  Warera Jeanne ~Shoujo Seisen Kageki~
- Berryz Koubou holds the record for being the group with the most appearances in Gekiharo stage plays at 7.
- Shimizu Saki and Sudo Maasa tie for the members with most appearances in Gekiharo at 9 each.
- Only one member from Morning Musume (Tanaka Reina) ever appeared in a main Gekiharo stage play despite being a main group of Hello! Project. Gogakuyuu featured other members, but it was a special collaboration.