The STAI is an instrument very used, generating different short versions. We found no short versions in which it is tests the fit for teenagers and college samples Spanish. The aim of this paper is to test which of the short versions proposed in the literature have a better fit in adolescents and college students. To do this, we applied the STAI to 482 adolescent students and 510 university students from different Spanish cities. Through AFC we evaluated five short versions of the STAI. At the university there are two models in which there is a good fit. In adolescents not fit any model. Maybe the emotional differentiation process explains that the found short versions (always with adults) are not valid in teenagers, and can be used with university students.