Background: Mixed martial arts (MMA) is experiencing a surge in popularity in Australia. Previous research has suggested knockout (KO) and technical knockout (TKO) are frequent outcomes during competition, raising concern about the brain health of athletes. This study aims to describe fight outcomes in Australian MMA and to explore differences in fight-ending outcomes between male and female athletes, amateur and professional competition, and different weight classes. Hypothesis: There is no difference in the incidence of KO/TKO between level of competition, sex, and weight class. Study Design: Descriptive epidemiology study. Level of Evidence: Level 3. Methods: Retrospective analysis of 143 Australian MMA events from 2020 to 2023 was conducted using video replay to assess fight outcomes between sex and level of competition. Binary logistic regression analysis was used to determine relationships between weight class and KO/TKO fight outcomes. Results: Male competition (34%) had a significantly greater number of KO/TKO secondary to head strikes fight outcomes compared with female competition (23%) (P = 0.01). The KO/TKO rate secondary to head strikes for amateur and professional male competition was 16.6 and 18.7 per 100 athlete-exposures (AEs), respectively. The amateur and professional female rate was 12.6 and 7.4 per 100 AEs, respectively. Amateur male light heavyweight and heavyweight, and professional male heavyweight were at greater odds of a KO or TKO compared with other weight classes in their equivalent level of competition. Conclusion: There is a sex and professional level disparity in the incidence of fight-ending head trauma in Australian MMA. The study findings highlight the urgent need for targeted safety protocols and medical oversight, particularly for men in heavier weight classes. Clinical Relevance: This study highlights the need for enhanced safety protocols and medical oversight in Australian MMA, particularly for male athletes in heavier weight divisions.