The aim of this study was to assess the effects of experience in mental imagery, imagery type (normal, bizarre, or mixed), and the repetition of mental imagery formation on imagery vividness. Two experiments were carried out: Experiment 1 consisted of a sample of 152 Spanish compulsory secondary education students who were shown a list of 16 simple sentences describing normal, bizarre, or mixed normal and bizarre situations prior to rating their imagery vividness. The procedure was repeated with the same imagery after a 24-hour interval. Subjects were also asked about their experience in using mental imagery. Subjects with mental imagery experience rated imagery vividness higher than inexperienced subjects. Image vividness scores were higher after repeating imagery formation than in the first imagery vividness ratings. Mixed and bizarre imagery obtained higher imagery vividness scores than normal imagery. In Experiment 2 a sample of 146 students, of the same academic background as in Experiment 1, were shown a list of 16 complex sentences under the same experimental conditions. Significant differences in imagery vividness ratings were observed in terms of experience and repetition of imagery. Ratings were higher for experienced than inexperienced subjects, and in the second ratings following the repetition of imagery formation. No significant differences in imagery vividness ratings were observed between both experimental groups in terms of imagery type. The results are discussed in the context of previous studies, and new lines of research are proposed.