B Based on WHO , 10-20% of children and adolescents are experiencing mental disorders and become a burden of disease (15-30%) over the last 3 decades. Assignments are given to kindergarten and elementary school students (37%) during online learning and also financial loss experienced by their parents can have an impact on both parents and children. This study will assess the most prominent behavioral aspects in students, parental stress levels, risk factors of parental stress and children beahviour and relationship between parental stress and children behavior during the COVID-19 pandemic. This study using a cross-sectional design to a population of 3rd to 5th grade elementary school students who conduct online learning with a sample size of 170 students using consecutive non random sampling method and analyzed using Chi-square test and Fisher test. The results showed that the most prominent behavioral aspects in students were emotional problems (17.6%), conduct problems (5.3%), hyperactivity-inattention (4.7%), prosocial ( 2.4%), and peer problems (0.6%). Most parents 97.6% experienced mild - moderate stress. Household conflict and lost father's income (p<0.05) are the risk factors of parental stress, meanwhile the risk factor of children behaviour only their age (p = 0.027). Also, there is no significant relationship between parental stress and children's behavior during the COVID-19 pandemic with p = 0.439. However, it was found parental stress perception was associated with emotional problems (p = 0.000) and conduct problems (p = 0.020) but was not associated with hyperactivity-inattention (p = 0.351), peer problems (p = 0.053), and prosocial (p = 0.197).