Most of the people who live in our country, Myanmar are farmers and they work mainly on farming and crop growing. Data mining can help farmers to increase crop yield in agriculture field of country development. Crops can be protected from pests by predicting and enhancing crop cultivation by using data mining approaches. The purpose of this paper is to study a comparison of two data mining approaches C5.0 and CART algorithms. This paper also presents oneR feature selection method for filtering crop pest dataset attributes instead of using full attribute set. C5.0 proved its efficiency by giving more accurate result rapidly and holding less memory while comparing the CART algorithm.