Isabwa, who helped Sharks to a third-place finish last season, returned back to his boyhood club after a turbulent season with Sharks following a lengthy battle with a nagging ankle injury last season.
The injury restricted the 2016 Vihiga United's top scorer with 10 goals, to just over 10 appearances for Sharks in the top flight league in 2017.
“Vihiga is like my home. Am going back to a place I know too well but am also cognizant of the fact that they are no longer playing in the NSL. This is KPL and I'm expecting tough games,” Isabwa told Goal.
“My goal now is to help the club stay in KPL next season but also surpass my previous achievements.
“Last season wasn’t a good one of the best for me. I battled injuries but now am all set.”
Vihiga United gained promotion to the Kenyan Premier League after lifting the lower tier National Super League.