"I will be number one, no matter who is second or third," she told reporters, adding that she didn't consider anyone competition.
She also announced her plans for her new role. "Like a woman takes care of her family and house sensitively and properly, in the similar manner I will make the city neat and clean. All problems will be solved very soon," she said.
Ms Gupta belongs to a family of BJP members and supporters and her husband Satish Bhatia is a former BJP lawmaker. She has been a BJP member since the party was founded in 1980.
Her rivals were Meera Vardhan of the Samajwadi Party and Prema Awasthi of the Congress.
"Our time has come," she had said when asked about a woman mayor for Lucknow, a city that has always been a VIP constituency and was once held by former prime minister Atal Behari Vajpayee.
Ms Gupta campaigned extensively for the polls and promised to make Lucknow a "clean, beautiful, safe, planned and smart city."