Objective: The present study aimed to assess complementary feeding practices and identify the potential risk factors associated with inappropriate complementary feeding in Indonesia for a nationally representative sample of births from 2004 to 2007. Design: The data source for the analysis was the 2007 Indonesia Demographic and Health Survey. Multiple logistic regression was performed to analyse the factors associated with complementary feeding, using individual-, household-and community-level determinants. Setting: Indonesia. Subjects: Children (n 4604) aged 6-23 months.Results: Multivariate analysis revealed that infants from poor households were significantly less likely to be introduced to complementary feeding (adjusted odds ratio, AOR 5 4?32; 95 % CI 1?46, 12?80) and meet the minimum dietary diversity (AOR 5 1?76; 95 % CI 1?16, 2?68). Mother's education (AOR for no education in dietary diversity 5 1?92; 95 % CI 1?09, 3?38; AOR for no education in meal frequency 5 2?03; 95 % CI 1?13, 3?64; AOR for no education in acceptable diet 5 3?84; 95 % CI 2?07, 7?12), residence and decreased age of the infant were negatively associated with minimum dietary diversity, minimum meal frequency and an acceptable diet. Infants aged 6-11 months were also significantly less likely to meet minimum dietary diversity (AOR 5 6?36; 95 % CI 4?73, 8?56), minimum meal frequency (AOR 5 2?30; 95 % CI 1?79, 2?96) and minimum acceptable diet (AOR 5 2?27; 95 % CI 1?67, 3?09). All geographical regions compared with Sumatra were more likely to give the recommended meal frequency and an acceptable diet to breast-fed children. Conclusions: Public health interventions to improve complementary feeding should address individual-, household-and community-level factors which significantly influence the introduction of complementary feeding. Complementary feeding intervention programmes in Indonesia should ensure that restraints on families with low socio-economic status are addressed. Infants aged 6-11 months and mothers with low education levels may also need special focus. Promotion strategies should also target the health-care delivery system and the media. Keywords Complementary feeding indicators Infant feeding Young child IndonesiaWhen breast milk alone is no longer nutritionally sufficient for an infant after 6 months of age, the initiation of complementary feeding allows the child to transition gradually to eating family foods. It is estimated that 6 % of deaths among under-5 s could be prevented through the achievement of universal coverage with improved complementary feeding alone (1,2) . The WHO infant feeding guidelines recommend that infants should be exclusively breast-fed for the first 6 months of life, after which complementary foods may be introduced in conjunction with continued breastfeeding to achieve optimal growth, development and health (3)(4)(5) . In many developing countries, complementary foods consist of cereals or starchy roots that have been prepared as a thin gruel. Coupled with very few feeds per day, the lac...