<![CDATA[The objectives of this study include: 1) to determine the effect of teacher professional competence on the learning discipline of junior high school students in Saipar Dolok Hole District; 2) to determine the effect of principal leadership on the learning discipline of junior high school students in Saipar Dolok Hole District; and 3) to determine the effect of teacher professional competence and principal leadership simultaneously on the learning discipline of junior high school students in Saipar Dolok Hole District. The method used in this study is quantitative with the Ex Post Facto quantitative method. The population is all junior high school students in Saipar Dolok Hole District totaling 745 people and a sample of 88 people was determined using the Slovin formula. The instrument trial was conducted on 30 students outside the research sample so that it was known that all research instruments were declared valid and reliable because they had met the validity and reliability value criteria. Data were collected with a closed questionnaire of 90 items. The results of the data analysis show that: 1) the Fcount value > Ftable (k; n-2) (2;86) is 58.312 > 3.15, thus it is known that there is a positive and significant influence of teacher professional competence on the learning discipline of junior high school students in Saipar Dolok Hole District. This influence is 40.4%, 2) Fcount value > Ftable (k; n-2) (2;86) is 33.541 > 3.15, thus it is known that there is a positive and significant influence of principal leadership on the learning discipline of junior high school students in Saipar Dolok Hole District. This influence is 28.1%, and 3) the Fcount value > Ftable (k; n-2) (2;86) is 33.058 > 3.15, thus it is known that there is a positive and significant influence of teacher professional competence and principal leadership simultaneously on the learning discipline of junior high school students in Saipar Dolok Hole District. The influence is 44.5%, thus Ha is accepted and H0 is rejected]]>
