The research objective was to analyze the effect of providing material about Basic Life Support (BLS) on increasing the knowledge of coaches. Methods: This study was an experimental study with one group pretest and posttest design. Subjects of the study were 10 male coaches from Aceh Province, aged 22-32 years, from 5 different types of sport, namely Rugby, athletics, Taekwondo, Archery, and Karate. Data analysis used descriptive analysis, chi-square (p<0.05), and paired sample t-test (p<0.05). The results showed that the average age was 26.7 years. 30% of the subjects had a high school degree, 50% of the subjects had undergraduate degree, and 20% of the subjects had a Master degree. The level of coach's knowledge about BLS was increased by 40.37% after receiving material about BLS. The knowledge level of the coaches was different before and after receiving education about BLS (56.67 and 79.55; p = 0.001). It was also related to the level of education (x² = 0.007*). Conclusions: The level of the coach's knowledge about BLS is related to education level. The coaches with undergraduate degree had better knowledge than others. The study concludes that providing BLS materials could effectively improve the knowledge level of the coaches from Aceh province.