Spanning over an area of around 10 sq km, Arumanai is in Kanyakumari District, Tamil Nadu. Kadayal is situated in the north, Edaikodu in the west, Ponmani in the east and Thiruvattar in the south-east. Thengapattinam, and Thriparappu Waterfalls are nearby.
The nearest airport is Trivandrum International Airport. Kuzhithurai Railway Station serves the town. Nagercoil Junction Railway Station is the nearest major railhead. Arumanai is easily accessible from Nagercoil and Nedumangad.