Longtarthepi is a village in Donka tehsil in district of Karbi Anglong, Assam, India. As per the data provided by Census of India in 2011, total population of Longtarthepi was 184 which includes 94 males and 90 females. Longtarthepi covers 39 ha area. Pincode of Longtarthepi is 782448.