Virendra Singh (55), Nirale (40), Rahimpal (25) and Ram Kumar (28), all residents of Etawah, were killed in the mishap, police said.
The two injured were rushed to a hospital and their condition was stated to be critical, they said.
All the occupants of the ill-fated vehicle were returning home after attending a marriage function in Ghaziabad.
As they reached Tappal area, their SUV developed some snag and it rammed into the divider and turned turtle.