Background: Emotions are potent modulators and motivators of the behaviour that the individual displays in the different situations they have to live and they can act as a protection factor or vulnerability of the adapted or maladaptive behaviour. This study focuses on anxiety in adolescence. Objectives. The objective is, through a longitudinal study, to analyse the psychological processes and emotions that facilitate the symptoms of anxiety and those which protect the adolescent from these symptoms. Material and Methods: 417 adolescents ( 192 boys and 225 girls) participated in a three-wave longitudinal study in Valencia, Spain. In the first wave, adolescents were either in the third year of secondary school (81 boys and 85 girls) or the fourth year of secondary school (111 boys and 140 girls). The mean age was 14.70 (SD = 0.68; range = 13-17 years). This study monitored participating adolescents for three years. Results: The results indicate a differential profile in the evaluated emotions according to sex, with the girls being the ones to experiment more anxiety and more empathy, while the boys show more emotional instability and aggression. Conclusions: It is concluded that the best predictors for anxiety are anger state, aggressive behaviour, empathic concern together with the lack of coping mechanisms focused on problem solving and the perception of stress as a threat.