Background: The inappropriate use of antibiotics significantly contributes to the development of antibiotic resistance. There is limited information about the use of antibiotics among parents from rural areas in Peru. This study aimed to describe the knowledge, attitudes and practices towards antibiotics among parents of children < 5 years of age from rural communities in Peru; to explore the association between knowledge and attitudes towards antibiotics and to explore determinants of low knowledge and self-medicating his/her child with antibiotics. Methods: Cross-sectional study in six rural primary health centres in Peru using a self-administered survey. Crude and adjusted Prevalence Ratios (PR), and 95% Confidence Intervals (95% CI) were calculated to explore determinants of low knowledge and of having self-medicated his/her child with antibiotics. Linear regression was used to explore the association between knowledge and attitudes. Results: A total of 231 parents were included. The largest gap in knowledge was among 183 parents (79%) who did not know that antibiotics cannot cure viral infections. The largest gap in attitudes was among 185 participants (80%) that did not disagree with “If I want my child to receive antibiotics, I would not be satisfied if the doctor refuses to prescribe them”. More than half of parents (n = 120, 52%) reported having self-medicated his/her child with antibiotics. A positive correlation was found between knowledge and attitudes (Coefficient 0.53, 95% CI 0.38–0.68) after adjusting for the age and the education of the parent. Parents who were < 20 years old were more likely to have low knowledge about antibiotics (crude PR 2.39, 95% CI 1.32–4.34) compared to those aged > 40 years. Parents who had self-medicated his/her child with antibiotics (n = 120, 52%) were more likely to have purchased antibiotics without prescription (aPR 2.70, 95% CI 1.74–4.19) and to have received antibiotics after the recommendation of a pharmacist (aPR 1.79, 95% CI 1.13–2.82). Conclusions: Knowledge about antibiotics among parents from rural settings in Peru is limited and highlights the need for educational interventions. Public health policies to limit the acquisition of antibiotics without prescription should be implemented.