Since motorcycle taxi drivers often work long hours, fatigue would affect their riding abilities, impacting crash risks. However, there is limited understanding about motorcycle taxi drivers' fatigue-related crashes. This study investigates self-reported fatigue-related crashes among motorcycle taxi drivers in Hanoi, Vietnam. Results from a survey showed that approximately 16% of the motorcycle taxi drivers reported fatigue-related crash involvement. It was also found that nearly 37% of all crashes reported by motorcycle taxi drivers were related to fatigue while riding a motorcycle taxi. Results of the heterogeneity-in-means random parameter logistic model suggested that working fulltime, more delivery trips, and overweight conditions were associated with increased likelihoods of fatigue-related crash involvement. Hybrid taxi drivers, who operate as either traditional or ride-hailing taxi drivers at different times, and most ride-hailing taxi drivers had a reduced likelihood of fatigue-related crash involvement when compared to traditional taxi drivers. Overall, this study has revealed a significant issue of fatigue-related crashes among motorcycle taxi drivers. Immediate interventions via publicity or educational campaigns should be considered by authorities to address this important issue. Ride-hailing companies should contribute by sending warnings of excessive riding hours to ride-hailing taxi drivers.