This qualitative research focuses on a case study that attempts to look deep into the complexities of an online Arabic course. The course encompasses eleven Arabic foreign language students. Online teaching has become tremendously pervasive in the last few years for a number of reasons such as time and place restrictions, cost, and autonomous learning. Finding effective ways for teaching language online is still an issue under investigation. However, transferring learning from face to face to online setting leads to complexities in both learning and teaching (Karakus, 2014). As a result, there is a need to investigate the online teaching setting with all its intricacies. This paper will attempt to explore such intricacies through Activity theory framework. This framework developed by Engeström in 1987 is thought to be the appropriate tool for understanding the relationship between the various components of this online course. This framework allows for exploring how the components of the online course interact together for revealing the relationship between them. Thus, it helps demonstrate the interplay between course components and the resulting complexities which allow for suggesting solutions to such complexities. The framework consists of seven components as follows: subject, tool, object, rules, community, division of labor, and outcome. Several research studies used this framework in order to explore and describe the implementation of new courses in certain contexts such as those done by: Edwards & Mutton, 2007; Ellis, 2007; Benson et al., 2008; Waters & Wall, 2008; Feryok, 2009; Feldman et al., 2010; Adriana et al., 2012 The main components of the target activity system under investigation are: 1) Subjects: Students and teacher, 2) objective and outcome: Understanding content, 3) Tools: Software and Blackboard, 4) Community: Online virtual environment, 6) Rules: Rules students should abide to in the course. Observations, open ended questions, and note taking are used for collecting data from students. In addition, recorded video sessions, written texts from journals and grades retrieved from instant feedback activities are used for data analysis. Exploring the complexities in the aforementioned online Arabic course is expected to facilitate the awareness of challenges and the reconfiguration of the course. This can lead to further development and course progression. Consequently, findings of this exploratory qualitative research are expected to enhance teaching Arabic courses online through suggestions that overcome online teaching complexities.