The present study investigates the effect of negative emotions (focusing on disappointment, sadness and regret) on cognitive schemas. The sample consist in students from the University of Bucharest (convenience groups). A univariate unifactorial experimental design was used, as the current study had one independent variable, negative emotions, and a dependent variable, cognitive schemas, which was measured with the Core Beliefs Questionnaire instrument. We applied T test for independent samples, using SPSS. The t test was statistically significant, t (45) = 2.57, p <0.05. The confidence interval (95%) for the difference between the averages is between 2.95 and 24.35. After applying the intervention, the evaluated sample (M = 43.17, SD = 29,074) showed a statistically significant difference compared to the control group (M = 29.52, SD = 11.257). The data collected support the main research hypothesis of the study, negative emotions can bring about changes in certain cognitive schemas by modifying, altering or disrupting them.