This review aims to evaluate the effectiveness of HIIT on basketball players' physical fitness and skill-related performance. This study adhered to the PRISMA guidelines and included randomized controlled trials (RCTs) that investigated the effects of HIIT on basketball players. The databases searched included Web of Science, Scopus, PubMed, and SPORTDiscus (up to 4 March 2024). The meta-analysis used a random-effects model, with effect sizes (ES) calculated for various performance outcomes. A total of 15 studies, with a low risk of bias or some concerns of bias, including 369 players (130 females, 239 males) at the developmental level, national level, and international level, were included in the systematic review, with 7 of these included in the meta-analysis. The systematic review indicated that HIIT significantly improved cardiovascular endurance, power, change of direction (COD) ability, linear sprint, and basketball skill-related performance. However, the effects on certain physical aspects such as VO_2max, the Yo-Yo intermittent recovery test level 1 (Yo-Yo IR 1), jump tests, ball throw test, 20-m COD sprint test, T-test, 20-m linear sprint, and basketball-specific skills such as shooting accuracy and passing were inconsistent. The meta-analysis revealed a very large effect on the Yo-Yo IR 1 (ES = 2.32; p = 0.000), a moderate effect on VO_2max (ES = 0.90; p = 0.000), T-test performance (ES = 0.91; p = 0.000), and CMJ height (ES = 0.76; p = 0.000), and a small effect on the 20-m sprint test (ES = 0.59; p = 0.006). HIIT appears to be an effective training method for improving general physical fitness and certain basketball-specific skills, particularly endurance, power, and agility. However, its impact on more skill-specific aspects, such as shooting accuracy and passing, requires further investigation. Coaches should consider supplementing HIIT with targeted skill training and carefully plan its timing, ideally incorporating HIIT during pre-season or off-season periods for optimal effectiveness. Further research is needed to explore the differential effects of HIIT across various age groups and playing levels.

• HIIT significantly improves cardiovascular endurance, power, change of direction ability, and sprint performance in basketball players, with particularly strong effects on endurance measures like the Yo-Yo IR 1.

• The effects of HIIT on basketball-specific skills like shooting and passing are inconsistent, suggesting that HIIT should be supplemented with specific skill training.

• Coaches should carefully time HIIT interventions, particularly during the season, and tailor them to the player's age and skill level for optimal benefits.