Mathematics learning is very important but it is felt very difficult for the students. Geometry is a part of mathematics learning. The connected mathematics project-based learning (CMP) is mathematics learning that raised everyday problems in life to explore mathematical ideas so that to foster the student-centered learning environment to solve their problems by an investigation. Mathematics learning that connected both concepts and what was seen in real life would make it easier for the students to understand the concept and develop it in the form of creation at the time of Covid-19 pandemic which was carried out in online and local culture. This research used 2 x 2 factorial that was mean 2 methods, namely the control class and the experimental class and then 2 learning materials (online and ethnomathematics). The population was the students of elementary school in Bengkulu City, namely the students in grade 5. The Samples were taken by using a group technique based on school accreditation. A sample of 120 students, namely grade 5 students of SDN 1, SDN 65, SDN 81, and SDN 103 Bengkulu City. The CMP learning used online media based on local culture as an experimental class and conventional learning as a control class. The research instrument used was an online test of the capacity to comprehend the geometric concepts. This instrument was analyzed by utilizing the ANCOVA statistical test. Based on the analysis results by using the Kolmogorov-Smirnov test, the data in this research was normal and homogeneous. Thus, it could be concluded that there was the effect of CMP in online learning with a local cultural approach on the capacity to comprehend the geometric concept of the normal score and also the understanding the concept of geomantic for understudies who educated utilizing the CMP learning that was higher than understudies taught by using the conventional learning. In addition, the average score of students' ability in understanding the concept of geometry among understudies who were given material based on local culture was higher than students who were given material that was not based on local culture with t count 2.169 and t table 2.042. It means that t count > t table.