Parents are active participants in their child's sport participation, as they experience cognitive and behavioural outcomes as a result of sport socialization. As such, parents may develop a social identity that is tied to their child's team membership. Despite this, the conceptualization and measurement of parental social identity in sport has received little attention. 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 sport team. Based on Cameron's (2004) three-factor model of social identity and the newly developed Social Identity Questionnaire for Sport (SIQS), we assessed competitive youth sport parents' perceptions of ingroup ties, cognitive centrality, and ingroup affect. Using confirmatory factor analysis, this factor structure was assessed in a sample of 788 hockey parents (Mage = 43.27, SD = 6.30; male = 401; female = 387). Confirmatory factor analysis indicated reasonable model fit (RMSEA = 0.087, CFI = 0.960, TLI = 0.934, SRMR = 0.039). Subsequent measurement variance testing for sex (i.e., male, female) and parents' previous experience with youth hockey (i.e., yes or no) evaluated configural, metric, and scalar variance consecutively. Results show strong measurement invariance across sexes and with regard to parents' previous experience in youth hockey. We discuss the implications and future directions of applying the SIQS to parents in youth sport.