The enterprise can implement Activity Based Costing System (ABC System) to determine the cost of the base or service price. This method is used to make a good decision regarding the cost of the base or service price in the hotel's diversity in providing products or services. This study is aim to determine the calculation and the differences of the base price of renting the hotel's room in Selecta Hotel (traditionally) and the calculation by using abc system. The results showed there were some differences between the method applied by Selecta Hotel and ABC System. Based on the result of calculations, there were differences between a lower price (undercosting) for six types of rooms namely Family, Deluxe, Superior, Executive, Suite and Exclusive type which were Rp 225.007,15, Rp 218.510,72, Rp 292.523,33, Rp 66.426,15, Rp 250.638,78, and Rp 132.460,68. While the two types of rooms had a higher price (overcosting) Cottage I and Cottage VII type. They are Rp 857,601.79 and Rp. 171,568.28.