The incident took place when the persons were on their way to Auraiya from Delhi in their car to attend a wedding, police said.
The car collided with a truck at Karhal crossing on National Highway-2 under Sirsaganj police station area, Superintendent of Police, Piyush Srivastava said.
Those killed were identified as Dharmendra (35), Akshay (22), Ramji (19), Vandana (6), Tanya (12), and Gudia (5).
The injured were rushed to a hospital and their condition was stated to be stable.