Power from hybrid renewable energy sources (RES) are increasing drastically in recent years but in mountainous regions it can play an important role where population is sparse and geographically isolated. This chapter aims to study first time the techno-economic feasibility analysis of photovoltaic (PV)-wind (W)-diesel (D), PV-D, PV-W, W-D, PV and W only with and without tracking systems for mountainous region of Sikkim in India. For this load demand of 88.9 kWh/day of hostel in National Institute of Technology Sikkim is used for analysis. The cost of Energy (COE) $/kWh for PV-D, PV-W-D, PV-W, W-D, PV and W are 0.284, 0.305, 0.334, 0.375, 0.377 and 0.687 respectively, showing PV-D combination has least COE and can be beneficial. PV-D combined with different tracking systems and it is found that horizontal tracking system is producing more power.