Modi will address a rally in Amethi on Monday, the last day of campaigning in the constituency which will go to polls on May 7.
Other senior BJP leaders including L K Advani, Sushma Swaraj and Arun Jaitley will also campaign for Irani.
Jaitley said senior party leaders will be campaigning for the favourite television "bahu" in the Gandhi stronghold.
BJP is giving all the push to the television actor-turned -politician for giving a tough fight to Rahul, whose campaign is being steered by his sister Priyanka Gandhi in the constituency.
Two-time MP from Amethi, Rahul Gandhi is locked in a triangular contest from the family pocket borough with Smriti Irani and Kumar Vishwas of Aam Aadmi Party pitted against him.
Though the Congress Vice President had won the seat in 2004 and 2009 elections with huge margins, Congress had lost in three of the five assembly segments falling under Amethi Parliamentary seat during the Uttar Pradesh Assembly elections in 2012.
The constituency is known as the seat of power of the Nehru-Gandhi political dynasty since 1980, when Sanjay Gandhi represented it once and later Rajiv Gandhi represented the seat four times.
Sonia Gandhi also represented the seat but later shifted to Rae Bareily, to vacate the seat for Rahul. Former prime minister Jawaharlal Nehru also represented the seat.