Unjanai is a village in Tiruchengode tehsil in district of Namakkal, Tamil Nadu, India. As per the data provided by Census of India in 2011, total population of Unjanai was 5,576 which includes 1,852 males and 3,724 females. Unjanai covers 1057.5 ha area. Pincode of Unjanai is 637205.