Michelle Sadio was killed as she stood among a crowd of mourners at the River of Life Elim Pentecostal Church in December.
28 year old Tahjin Sommersall from Feltham, Shaquille Sutherland and Perry Allen-Thomas from Wembley deny.
Mr Sommersall also pleaded not guilty to possessing a firearm.
They appeared at the Old Bailey via video link.