This study investigated the relationship between family factors and students’ scientific literacy performance in Hong Kong, which has excelled in science performance in previous international studies. Data were obtained from the 2006 Programme for International Student Assessment. Multilevel analysis was used to examine the relationship between parental involvement and investment and students’ scientific literacy performance. It was found that students’ scientific literacy performance, which was measured by their science achievement and self-efficacy towards science, were significantly associated with certain types of parental investment and involvement even after controlling background factors of both students and schools. Parental investment in cultural resources and parental involvement in terms of organising science learning enrichment activities at an early age were found to be significantly associated with students’ scientific literacy performance. Activities that could be provided at an early age (e.g. watching TV programmes about science, reading books on scientific discovery, watching, reading or listening to science fictions) were found to be highly effective activities for promoting children’s science achievement and self-efficacy.