Wonderful Hearts (ワンダフルハーツ) was a Hello! Project concert group. Since 2006, Hello! Project had been split into Wonderful Hearts and the Elder Club, but Wonderful Hearts was the only remaining unit upon the graduation of Elder Club on March 31, 2009.
Hello Pro Egg members usually appear with Wonderful Hearts as backup dancers.
As of January 2010, Wonderful Hearts has been disbanded as a concert unit due to the creation of Hello! Project Mobekimasu.
- Last Remaining Members
- Morning Musume
- Berryz Koubou
- Mano Erina (transferred from the Elder Club in 2008)
- Hello Pro Egg
- 1st Gen: Tanaka Anri, Sengoku Minami, Furukawa Konatsu, Sainen Mia, Mori Saki, Kitahara Sayaka, Saho Akari, Sekine Azusa, Okai Asuna, Maeda Irori, Arai Manami
- 2nd Gen: Komine Momoka
- 3rd Gen: Kikkawa Yuu (joined in 2007)
- 4th Gen: Fukumura Mizuki, Kaneko Rie, Takeuchi Akari (joined in 2008)
- 5th Gen: Miyamoto Karin (joined in 2008)
- 6th Gen: Sato Ayano (joined in 2009)
- 7th Gen: Hirano Tomomi, Katsuta Rina (joined in 2009)
- 8th Gen: Takagi Sayuki (joined in 2009)
- Former Members
- From Morning Musume
- 7th Gen: Kusumi Koharu
- From W
- From ℃-ute
- From Hello Pro Egg
- Transferred to the Elder Club