Aim The dramatic rise in childhood obesity incidence in developing countries is related to nutrition and lifestyle transition. The aim of this review was to evaluate the quality and reporting of dietary assessment methods used in studies examining the relationship between dietary outcome and childhood obesity in developing Asian countries. Methods A three-step search strategy was conducted in databases between inception and 2011 with an English language restriction. Inclusion criteria were any cross-sectional or cohort studies in children =18 years who resided in developing countries in Asian region that included reporting on dietary intake. Papers were screened with standardised tools for quality and dietary methodology reporting. Results The search process identified 2080 studies and 15 studies (in 16 articles) met inclusion criteria. The most commonly used dietary assessment method was dietary questionnaires (n = 10), followed by 24-hour diet recall (n = 4), food frequency questionnaire (n = 3) and an unweighed food record (n = 1). For dietary methodology reporting, 12 out of 16 articles were rated as 'poor', 3 rated as 'acceptable' and 1 as 'excellent'. Conclusions The quality rating was influenced by the dietary assessment tool chosen, and a quality rating of 'poor' was mostly obtained by studies using non-standardised, non-validated study-specific dietary questionnaires. Significant gaps were identified in dietary intake methodological quality and hence, there is an urgent need for valid dietary measures and reporting of dietary intake among overweight children for studies conducted in Asian region.