Head coach Dave Edmondson has left Bristol Academy after 18 months, with the club bottom of the Women's Super League.
A statement highlighted concerns that results were "not aligned" with the club's ambitions.
"It was felt by both parties that a new coach should be appointed," it read.
Assistant first team coach Lauren Smith will take over as interim coach of the Vixens, who have lost their opening three matches of the new season.
She will be assisted by goalkeeping coach John Granville, who was previously the Trinidad national team manager.
Bristol chairman Simon Arnold said: "Success at Bristol Academy is judged by what happens within our whole club.
"I think it is clear to everyone we had started to lose our way and, despite Dave's efforts, we were seeing a decline in areas which need to be addressed sooner rather than later.
"It was a difficult decision for us as he is an honest, hard-working and talented coach but sometimes things just don't happen the way you want them to."
Edmondson was appointed in January 2014 after spells managing in New Zealand and Australia.