First aid given by laypersons in trauma cases has more mistakes. Injuries that occur require appropriate treatments. First aid education is part of health promotion. First aid guideline application (FAG) is a new education method. This study aimed to analyze the difference in students' knowledge, attitude and skill improvement in first aid by using FAG application. The study design used quasy experiments using control and experimental group. Research location was in SMP Negeri 2 Jember. There were 120 respondents taken by purposive sampling technique with two groups. Data analysis used independent t-test. Statistic analysis using independent t-test. Variables of knowledge obtained the p-value = 0.008, meaning there is a significant increase of knowledge after getting first aid education by using the application of FAG. The attitude variable got a p-value = 0,023, meaning that there is significant attitude improvement after getting first aid education by using the application of FAG. Skill variable found that p-value = 0,035 meaning that there is significant skill improvement after getting first aid education by applying FAG. There are differences in variables of knowledge, attitudes and skills among Junior High School students between the intervention and control groups.