Drawing from theory of the multidimensional nature of social identity, the purpose of this study was to assess an adapted measure of social identity in sport that captures the extent to which parents identify with their child's team. Using the Social Identity Questionnaire for Sport (SIQS) with items specifically modified for parents, we assessed competitive youth sport parents' perceptions of ingroup ties, cognitive centrality, and ingroup affect. Using an exploratory and confirmatory analysis process, a conceptually grounded three-factor structure was supported in a sample of 788 ice hockey parents. Measurement invariance testing found strong invariance for the measurement tool based on participants' biological sex, previous sport experience, and proximal competition outcome. Finally, differences emerged when comparing latent means across their child's most recent game outcome. Taken together, this study offers a novel tool to better understand and measure perceptions of social identity among sport parents.