The present study explored complex aspects of selfregulation involved in managing females’ oral sex behaviour in ego depletion and under relationship power pressure. Online survey on sexual behaviour was completed by 248 female university students aged 18-24. Impulsivity, normative beliefs, attitudes to oral sex, motivation to control sexual behaviour, trait self-control and sex-related self-control were measured. Stepwise hierarchical regression was used to identify the predictors of engagement in oral sex. Causal relationships between the main predictors were explored by structural equation modelling (SEM). The study found sex-related self-control and motivation to control sexual behaviour to be the two important components of self-regulation serving the same purpose but working in different ways. The effect of sexrelated self-control on oral sex behaviour varied depending on females’ individual trait self-control and relationship power pressure. Besides the main effects of self-control and motivation, the important role of attitudes to oral sex and normative beliefs in engagement in oral sex behaviour was demonstrated. Exploring relationship between all variables involved in regulating oral sex behaviour proposed the path by which they can influence engagement in oral sex. Findings from this study have implications on theoretical and practical level.