The study determined the parent-teacher collaboration in a modular learning approach in C.M Recto Elementary School during the School Year 2020-2021. The study used a mixed method of qualitative and quantitative research design. Survey and unstructured interviews were utilized in gathering the necessary data from the respondents. 28 parents and 5 teachers were involved in this study. The data collected were analysed using weighted mean to determine the parent-teacher collaboration along with instructional support, supervision and monitoring as well as the effectiveness of modular instructional material and learning outcomes of the pupils. Frequency and ranking were used to determine the challenges encountered by the parents in modular instruction.