Extant research has consistently demonstrated that both irrational and rational beliefs contribute to the occurrence and persistence of procrastination. Most of these studies have focused on the role of general irrational and rational beliefs, without addressing domain-specific beliefs that may influence academic procrastination. This cross-sectional study aims to fill that gap by investigating the relationship between irrational/rational academic beliefs, fear of failure, and academic procrastination in a sample of undergraduate students (N = 354). The current findings suggest that irrational academic beliefs are indirectly associated with academic procrastination through fear of failure. Furthermore, the positive relationship between irrational academic beliefs and academic procrastination via fear of failure differs based on the level of rational academic beliefs. These findings suggest that interventions designed to improve domain-specific rational academic beliefs and reduce fear of failure may help prevent or reduce academic procrastination, especially among undergraduates with high levels of irrational beliefs.