Larry Masashi Ōiwa, born September 23, 1975, is a Japanese designer and voice actor from Shiga Prefecture. A graduate of Musashino Art University's Department of Architecture, he works as a sports uniform designer for professional baseball teams but has also built a parallel career as a voice actor for Flash animation and television.

Ōiwa made his voice acting debut in the anime series The World of GOLDEN EGGS, which began airing in 2004 on networks such as Kids Station and MTV. He was cast in the series due to his prior acquaintance with the show's planner and character designer, Aya Fumihara. In The World of GOLDEN EGGS, he voiced multiple characters, including the role of Rose, and initially performed under the name LARRY.

Beyond his debut series, Ōiwa has taken on a variety of voice roles. He appeared in the 2012 collaborative promotional video Barcode Footballer, voicing characters in several commercial segments. From 2012 to 2014, he voiced the title characters in the television program Sumaho POLICE on TV Asahi, also contributing as a designer for that project. Starting in 2013, he has performed occasional voice work for the Fuji TV series Kamiusagi Rope, voicing a police officer and a friend of Akira's older sister. Since 2014, he has been the voice of Mezamashi-kun for the Fuji TV programs Mezamashi TV and Mezamashi Do you bi. In 2017, he appeared in the LINE LIVE exclusive program Kamiusagi Rope: Eiga Bangumi o Anime de Namajikkyou tte Majissu ka!?, again voicing the friend of Akira's older sister.

Ōiwa has served as the Master of Ceremonies for the Ryujin Stage at the Inazuma Rock Festival since 2015. He has also passed the Level 4 Baseball Knowledge Test. While voice acting is a significant part of his work, his professional background is rooted in design, having created uniforms for numerous Japanese professional baseball teams including the Tokyo Yakult Swallows, the Tohoku Rakuten Golden Eagles, and the Saitama Seibu Lions.