A Genre Based Approach (GBA) is the concept of teaching to teach students in the text level by involving the stages of teaching that follows the concept of scaffolding. Some scholars had tried to contextualize, and to see the portrait of how GBA implemented in the teaching of writing in various levels. However, the implementation and the portrait on how GBA is used to scaffold students in online learning has not been studied. As a result, this study aimed to investigate the way teacher implements GBA to scaffold students writing in online learning. This study employed qualitative research design embracing case study approach and involved 1 teacher and 20 students enrolling in a junior high school in Bandung. The data analyzed by using a technique suggested by Miles and Huberman (1994). The result of the analysis showed that in online learning GBA is less effective to scaffold students in the teaching of writing. It is due to the teacher and students do not interact directly and there are several stages of GBA that are difficult to be implemented in online learning. It is recommended that future related research should be conducted in more diverse of educational settings in online learning.