The aim of this study is to evaluate the psychometric properties of Mathematics Anxiety (MA) questionnaires based on the psychological state-trait anxiety model. Therefore, the trait-Math Anxiety Questionnaire ( trait-MAQ) and the state-Math Anxiety Questionnaire ( state-MAQ ) were examined in a sample of Chilean school-aged children ( N  = 430, M age = 10.09, 259 females and 171 males). Data analysis was performed using Exploratory Structural Equation Modeling (ESEM). Consistent with previous findings, the results corresponding to the selected model for trait-MAQ show the presence of two factors: unhappiness and worry, and the results corresponding to the selected model for state-MAQ show the presence of a single factor, both immediately prior and after the completion of a mathematical test. Additionally, measurement invariance among participants classified by gender was confirmed by Multigroup Confirmatory Factor Analysis (MCFA), and gender differences were reported with males outperforming females. The correlation among trait- and state-MA scales was moderate. These results are important evidence of the validity of the analyzed questionnaires. To our knowledge, this study is the first adaptation and validation of the MAQ’s in Spanish. Given the profound state-trait discrepancies in MA research, it is clear that valid diagnostic tools for state and trait MA are needed for the development of MA research in Latin American countries such as Chile. Furthermore, the questionnaires are useful for gaining new insights into gender differences in MA.