The aim of this study is to find evidence of factorial validity, measure equivalence by gender, and internal consistency of the Mental Health Continuum-Short Form (MHC-SF) in a sample of Ecuadorian teenagers. The study uses a psychometric design to explore the validity and reliability of the measure. Participants of the study were 1154 teenagers between 14 and 19 years of age (mean = 15.69 years; sd = 1.06). In total, 67.7% of participants were women and 32.3% were men. Participants came from 21 cities across Ecuador. This study found that the most appropriate fit for the factorial structure of the MHC-SF is a hierarchical factorial structure with three first-order factors and one second-order factor. The questionnaire presented strict measure invariance amongst women and men and showed differences (p < 0.05) for the latent variables related to the emotional well-being factor. Additionally, the study found that the MHC-SF has high internal consistency. The MHC-SF is a valid measure to evaluate the well-being of Ecuadorian teenagers.