The swearing-in will be held in Sector 5 of Panchkula town adjoining Chandigarh. Haryana Governor Kaptan Singh Solanki will administer the oath of office to Khattar.
Departing from protocol, Prime Minister Narendra Modi will attend the oath taking ceremony.
This is the first time that a chief minister is being sworn-in at a public ceremony instead of the event being held at the Haryana Raj Bhavan here. BJP leaders said that nearly one lakh people could attend the ceremony at the Sector 5 Mela Ground.
"People are going to come in big numbers. Common people will be able to see the ceremony for the first time. We are making full arrangements for the event," senior BJP legislator Anil Vij, who is tipped to become a minister Sunday, said after reviewing arrangements in Panchkula.
Panchkula Saturday looked like a fortress with security personnel spread through the entire town, especially the areas around the Sector 5 venue.
Prime Minister Modi is likely to arrive at the Chandigarh airport before proceeding to Panchkula, 15 km from here.
"The ceremony is going to be a big event. Top leaders will be attending it," state BJP president Ram Bilas Sharma said.
Khattar will be the first BJP chief minister of Haryana since the state's inception in 1966.
Chief Minister-designate Khattar, a former Rashtriya Swayamsewak Sangh (RSS) pracharak, contested and won his first election from the Karnal assembly seat. He was chosen as leader of the BJP legislative party Tuesday.
The BJP, which till now used to play second fiddle to other regional parties in the state, created history by winning a majority 47 seats in the Haryana assembly polls.
BJP leaders said that chief ministers of BJP-ruled states are also likely to attend the swearing-in ceremony. These include Shivraj Singh Chouhan (Madhya Pradesh), Vasundhra Raje (Rajasthan), Raman Singh (Chhattisgarh) and Anandiben Patel (Gujarat).
Top BJP leaders, including national president Amit Shah, union ministers, Rashtriya Swayamsewak Sangh (RSS) leaders and others are also likely to attend the ceremony.
Union ministers Maneka Gandhi, General VK Singh, Krishan Pal Gurjar, Rao Inderjit and others are also likely to attend.