Chief Minister N Chandrababu Naidu suffered an injury to his right collar-bone as he headed to the temple in Tirupati, about 500 km from the state capital Hyderabad.
"We suspect the work of leftist extremists," Andhra Pradesh police chief A R Sukumara said, as experts inspected one of the cars in Naidu's motorcade completely mangled by the blasts.
No one has claimed responsibility for the blast.
Activists of Naidu's regional Telugu Desam party, meanwhile, took to the streets and smashed windscreens of buses in the pilgrimage town in rage over the assassination attempt, witnesses said.
The state's banned, but dominant People's War Group Maoist force frequently attacks police and other government sites in their decades-old fight that they claim is on behalf of landless farmers.
Naidu, one of India's most high-profile state leaders, is best known for championing Hyderabad's hi-tech industry and his name has frequently been mentioned for national positions.
Tirupati, a temple town built in the 12th century, is a top pilgrimage site drawing thousands of visitors daily.