This study aims to support students’ proportional reasoning in comparison problems using Palembang culture as context and PMRI approached. Six students of 7th grade were participated. We used design research as research approach, a Hypothetical Learning Trajectory (HLT) was develop and a set of activities using Palembang culture as context, such as ketek’ fare, empek-empek’ price, lempok’ price. Theoretical development is driven by an iterative process of designing instructional activities, performing teaching experiments and conducting retrospective analysis in order to contribute to Local Instruction Theory (LIT) to support students’ proportional reasoning in comparison problem. Data collected by making video recording about actual teaching and learning in classroom, collecting students’ worksheet, giving pretest and posttest, interviewing students. The designed HLT compared Actual Learning Trajectory (ALT) during pilot experiment to analyze whether the students learned or did not learn from what we had designed in the instructional sequence. Retrospective analysis of pilot experiment showed that by using Palembang culture as context can support students’ proportional reasoning in middle school to solve comparison problems.