Nowadays it is imperative to have predictors that allow an early and accurate detection of bipolar disorder, in general and bipolar type II disorder, in particular. Affective temperaments refer to different types of emotional reactivity, which are temporarily stable throughout the life cycle and demonstrate a relevant biological basis. Given the lack of previous research, possible relations between the onset age of 32 euthymic patients diagnosed with bipolar II disorder, and the cyclothymic, depressive, irritable, anxious and hyperthymic affective temperaments features were explored. The participants had an average age of 51.5 (interquartile range: 8) and 65.6% of the sample were men. A high and significant inverse correlation was found between the onset age of bipolar disorder and depressive temperament. Between cyclothymic, irritable and anxious temperaments, correlations were statistically significant, although moderate and inverse. Hyperthymic temperament did not significantly correlate with the onset age. When performing multivariate linear regression analyses, no satisfactory models were found. The systematic evaluation of affective temperaments, in those individuals who are prone to develop an affective disorder, should be included in the set of common evaluation techniques.Actualmente es imperante contar con indicadores que posibiliten realizar una detección temprana y correcta del trastorno bipolar en general, y del tipo II, en particular. Los temperamentos afectivos constituyen estilos de reactividad emocional temporalmente estables a lo largo del ciclo vital, con una importante base biológica. Dada la escasez de investigaciones al respecto, se exploraron posibles asociaciones entre la edad de inicio de 32 pacientes eutímicos con diagnóstico de trastorno bipolar tipo II y los temperamentos afectivos ciclotímico, depresivo, irritable, ansioso e hipertímico. Los participantes presentaron una edad media de 51,5 años (rango intercuartil 8) y el 65,6% de la muestra estuvo constituida por hombres. Se encontró una correlación inversa elevada y significativa, entre la edad de inicio del trastorno bipolar y el temperamento depresivo. Entre los temperamentos ciclotímico, irritable y ansioso, las correlaciones fueron significativas pero moderadas e inversas. El temperamento hipertímico no mostró una asociación significativa con la edad de inicio. Al implementar análisis de regresión lineal multi-variados, no se encontraron modelos satisfactorios. Evaluar los temperamentos afectivos de manera sistemática, en individuos vulnerables a presentar un trastorno afectivo, debiera ser incorporado al conjunto de técnicas de evaluación habituales.