There is growing interest in the area of elite athlete mental health, however brief, valid and reliable screening instruments designed to identify early indictors of athlete-specific distress and potential mental health symptoms are lacking. This study sought to develop a brief screening instrument for athlete populationsthe Athlete Psychological Strain Questionnaire (APSQ)and examine convergent, divergent and construct validity. A twostage psychometric validation study was undertaken. Self-report data was collected from 1,007 currently competing Australian elite male athletes (M = 23.67, SD = 4.16). The sample was randomly partitioned into calibration (n = 497) and validation (n = 510) samples. Exploratory and confirmatory factor analysis, and tests of differential item functioning were conducted. Exploratory factor analysis, with parallel analysis, conducted on the calibration sample supported a three-factor solution, with subscales assessing Self-Regulation, Performance and External Coping accounting for 50.44% of total scale variance. Confirmatory factor analysis supported this three-factor model, yielding excellent model fit indices (CFI = 0.976, TLI = 0.966, RMSEA = 0.055, SRMR = 0.032), with the Bayesian Information Criterion supporting the superordinate structure. Differential item functioning analysis indicated item-equivalence relative to athletes' level of education and ethnicity. As predicted, a multivariate effect indicated higher APSQ scores for currently injured athletes (p = .040) with a univariate effect on the Performance subscale. The APSQ may help identify early symptoms of athlete psychological strain facilitating timely management. Replication and validation studies in broader samples, including female athletes and comparison with other athlete-specific, coping and stress measures are needed.