Within a rapidly changing cultural and socio-economic context, young people in China are increasingly engaging in romantic experiences and sexual behaviours with consequences such as unwanted pregnancies and sexually transmitted infections. Across a range of contexts, parental communication about sexuality has been recognised as protective in terms of increasing the likelihood of sexual abstinence and safer sexual practice. This study focuses on the factors shaping parent-adolescent communication about sexuality. Thirty-eight young people and twenty-seven parents, recruited from two high schools in a Northern-Eastern city of China, were interviewed. Thematic analysis of their interview responses was conducted using a social constructionist framework. Four main themes were identified: timing; discomfort and uncertainty; assumptions; and the parent-adolescent relationship. Findings suggest that communication between parents and children is influenced by individual as well as interpersonal factors and factors relating to the broader Chinese sociocultural context. To facilitate communication, both parents and young people need support from health and other professionals, while parents need more help and support in overcoming historical, social and cultural barriers to open communication about sex.