The General Certificate of Education (Ordinary Level) (G.C.E O/L) examination is the first most important public certificate examination in Sri Lanka. Most of the candidates „fail‟ the G.C.E (O/L) examination due to their failure in Mathematics, leaving them without any viable option for their future. Identification of factors related to the results of Mathematics is essential to rectify this problem. This paper presents some findings of a study carried out in 2008 to explore the factors related to the results of Mathematics of the G.C.E (O/L) examination. The necessary data were collected from a survey conducted in the Piliyandala Educational Zone. The components of the syllabus that are most weighted in the marking scheme and the components preferred by the students were identified. The external factors that are associated with Mathematics marks were also identified through analysis of variance and regression analysis. Findings are useful to those who design curricula as well as to the teachers and parents.