Introduction. The negative effects of anger on health highlight the value of developing short, reliable, and valid instruments that allow its assessment whether for the purpose of research, clinical diagnosis, and/or evaluation of interventions aimed at reducing it effectively. Objective. The primary aim of this research was to determine the construct, convergent, and discriminant validity, as well as the factorial invariance, of a new scale to measure anger proneness. Method. A confirmatory factorial analysis was used. Results. An online nonprobability sample composed of 457 participants (35.2% men and 64.8% women), with a mean age of 36.87 years (SD = 12.513) was recruited. The unidimensional model of the García's Brief Scale for Assessing Anger Proneness (APS-G scale) shows a good data fit (df = 2; χ2 = 5.515; χ2/df = 2.575; CFI = .993; GFI = .996; RMSEA = .051; SRMR = .0193). There are factorial, configural, metric, unrestricted, strong, and strict factorial invariances between men and women. Likewise, a positive correlation coefficient exists between the APS-G scale and the State-Trait Anger Expression Inventory-2 (STAXI-2) (r = .561; p < .01); on the other hand, there is a negative correlation coefficient between the studied scale and the Satisfaction with Life Scale (SWLS) (r = -.179; p < .01). Discussion and conclusion. A new reliable and valid instrument to measure anger proneness has been created, and its use is proposed for research and screening purposes with Spanish-speaking population.