ABSTRACT This nal project discusses the sums of p-tribonacci numbers. This sum for- mula is obtained and proved by using the concept of p-tribonacci matrix and p-tribonacci triangle. This is a review of Kuhapatanakul's paper [East-West Journal of Mathematics, 14 (2012), 144-153]. Keywords: Tribonacci numbers, p-tribonacci numbers, p-tribonacci matrix, p-tribonacci triangle