Few studies have investigated the effect of maternal factors on child eating practices. Our study aimed to explore mother–child dietary behaviours and their associations with socio-demographic factors. A cross-sectional analysis was conducted using data from control participants (n 243) in the Healthy Beginnings Trial, which involved first-time mothers and their 2-year-old children. Mother–child dietary behaviours were assessed using short dietary questions (short FFQ) and their associations with socio-demographic factors were examined using binary logistic regression. The dietary intake of 2-year-old children was characterised by low vegetable consumption and high discretionary food intake. In multivariate analysis, lower-income mothers (<Australian $40 000 per annum) reported their child was more likely to consume less fruit (<1 serve/d) (adjusted OR (AOR): 5·83; 95 % CI 1·49, 22·80) and ate hot chips more frequently (≥2 times/week) (AOR: 4·80; 95 % CI 1·28, 18·04), compared with higher-income mothers (≥Australian $40 000 per annum). Younger mothers (<25 years) reported their child consumed more sugary drinks and soft drink (>0·5 cups/d) AOR 2·93 (95 % CI 1·03, 8·35), compared with older mothers (≥25 years). Non-Australian-born mothers reported their child consumed more fruit juice (>0·5 cups/d) AOR 2·04 (95 % CI 1·02, 4·05), sweet snacks AOR 1·96 (95 % CI 1·02, 3·76) and fast food (≥2 times/week) AOR 3·67 (95 % CI 1·29, 10·43) compared with Australian-born mothers. Significant positive correlations between maternal and child dietary intake were observed for all dietary variables except milk, with the largest association for fast foods (Pearson’s r 0·52, P<0·001). This study shows that maternal factors are associated with child dietary behaviours. Targeting young mothers (<25 years) of potential disadvantage, before commencement of early feeding practices, has the potential to improve children’s diets.