<![CDATA[Mathematics learning outcomes of fifth-grade students at MI Khoiru Ummah Pekanbaru remained low: a preliminary review showed that 71.05% of the students scored below the minimum mastery criterion (KKM) of 75, with an average of 49.71, while rewards were given only spontaneously and punishment was applied inconsistently. This study aimed to describe how reward and punishment were implemented in mathematics learning and to examine their effect on students' learning outcomes on the Greatest Common Factor (GCF). A quantitative quasi-experiment with a Nonequivalent Control Group Design was conducted with 38 students selected through saturated sampling: class VA (18 students) as the experimental group and class VB (20 students) as the control group. Data were collected through a valid 20-item multiple-choice test (Cronbach's Alpha = 0.896), observation, and documentation, and analyzed with the Wilcoxon test, the Mann-Whitney U test, and N-Gain using SPSS 27. The mean score of the experimental class rose from 65.56 to 88.06 and its mastery rate from 44.4% to 94.4%, whereas the control class rose from 65.50 to 81.25. The Mann-Whitney U test produced U = 95.000 and Asymp. Sig. (2-tailed) = 0.011 < 0.05, so the alternative hypothesis was accepted. The mean N-Gain of the experimental class (0.52) exceeded that of the control class (0.41), both in the moderate category. Planned and consistent reward and punishment therefore had a positive and significant effect on mathematics learning outcomes, and the greatest benefit was felt by students with low initial ability.]]>
