The purpose of this study was to evaluate the dental arch relationship of non-syndromic Malay unilateral cleft lip and palate children and assess the various congenital and postnatal treatment factors that affect dental arch relationship. Study models of 107 UCLP children were included in this study that was treated in Hospital Universiti Sains Malaysia over a period of 10 years (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012). The mean age was 7.69± 2.46 (mean± SD). The dental arch relationship was assessed by mHB scoring system which comprises five categories; namedexcellent; good; fair; poor and very poor. All the subjects were divided into two groups; favorable (category ratings excellent, good and fair) and unfavorable (category ratings poor and very poor) groups. The mean mHB score was -10.7. Total 60 subjects (68% of all subjects) were categorized into unfavourable group (category ratings poor and very poor) using mHB scoring system. Intra-and inter-examiner agreements were very good. Cheiloplasty seemed to be correlated with favourable dental arch relationship using crude regression analysis but no significant associations were found. This multivariate study shows no significant association between various congenital and postnatal treatment factors and dental arch relationship.