The existence of WhatsApp Group is needed distance learning during the Covid-19 pandemic. The purpose of this study was to find out the perception of EFL students and challenges that EFL students faced on using WhatsApp Group during the Covid-19 pandemic. This research used a case study qualitative research design. The research subject was 2 EFL students as the active and the passive based on as initiator in WhatsApp Group that was from fifth semester of English Department Mulawarman University. The researcher used observation and interview as instruments of this study. The result showed that the active participant and the passive participanthad positive perception that was related to positive feeling, kinds of communication, initiation and response, effective as communicational tool, task and material technically and language use on using WhatsApp Group during the Covid-19 pandemic. Moreover, the negative feeling on using WhatsApp group wasnot easy to conduct group division and distraction of notification when lecturing on WhatsApp Group. The language barrier was the challenge on using WhatsApp Group of initiation and response. It can be concluded that WhatsApp Group is a handy online application for distance learning to ask and give information about task and material during the Covid-19 pandemic.