This study aims to determine the perceptions of science teachers in compiling student learning outcomes instruments online, the obstacles faced by Science Teachers in making student learning outcomes instruments online. This research uses a quantitative approach with a descriptive research type. The sample in this study were 11 teachers of science subjects. Research data collection techniques, through filling out questionnaires, interviews and documentation studies. The results of the study show that the online science learning outcomes instrument at SMA Negeri 6 Banda Aceh has been prepared very well. The teacher's ability to plan an online science learning outcome assessment instrument at SMA Negeri 6 Banda Aceh has been carried out in the very high category. However, some of the obstacles faced by teachers in developing online science learning assessment instruments include: difficulties in carrying out the assessment because it is done online considering that this is the first time this online assessment has been carried out, however, according to the results of interviews, teachers at SMA Negeri 6 Banda Aceh, especially those who teach science subjects, are very motivated because this is a challenge in applying technology in learning; requires a longer time allocation in compiling instruments for assessing student learning outcomes so that it has an impact on the allocation of learning time which is limited and insufficient in conducting student assessments.