Background Childbirth fear and interventions during childbirth might be related to the mindset and knowledge non-pregnant women have regarding childbirth. Non-pregnant women before their first birth experience may be particularly at risk for childbirth fear. Methods The present study examined the expressions and associations of birth-related mindset, knowledge, and fear among 316 young, non-pregnant women without birth experience. They participated in a cross-sectional online study and completed the Childbirth Fear Prior to Pregnancy, the Mindset and Birth Questionnaire, and a birth knowledge test. Results Most women (44%) had a natural mindset and low fear, 29% had a medical mindset and low fear, 8% natural mindset and higher fear, and 19% medical mindset and higher fear. There were no differences in knowledge between the four groups. Some gaps in knowledge appeared concerning signs of beginning birth, and non-medical approaches to pain relief. From women with natural mindset and low childbirth fear, a higher percentage (13%) has already watched a birth, as compared to the other groups. Natural mindset was associated with lower childbirth fear, whereas knowledge was independent from childbirth fear. Higher knowledge was low associated with natural mindset. Mindset and childbirth fear were independent from age and education degree. Conclusions Gynecologists, midwifes and other health professionals may develop an awareness for birth as a natural event in their non-pregnant patients, and take birth-related fear into account in their counseling, with focus on women’s self-efficacy and non-medical approaches to pain relief.