Science competitions target students interested in science with the aim to support them in developing science competence and career aspirations. Contrary to the common belief that science competition participants are exceptionally competent and strongly motivated to pursue a science career, there is growing evidence that the entirety of participants is rather heterogeneous in terms of their cognitive and affective characteristics. For science competitions to better support all participants in developing competence and career aspirations, a better understanding of the cognitive and affective characteristics of the entirety of participants is required. This study examined the Physics Olympiad as a specific type of science competitions, leading to a nuanced characterisation of N = 155 Physics Olympiad participants. Latent profile analyses revealed four participant profiles distinguished by specific patterns in cognitive abilities, physics interest, and physics self-efficacy. Profiles differed in their performance in the competition and their physics career aspiration. Grade level, gender, previous participation in the competition, and teacher support explained differences in profile membership. Our findings emphasise that Physics Olympiad participants are a heterogeneous group with varying needs and offer implications for more individualised support activities to better support the entirety of participants in developing science competence and career aspirations.