Social network platforms have increased and become very popular in the last decade; they allow people to create an online account to then interact with others creating a complicated net of connections. LinkedIn is one of the most used social media platform, created and used for professional purposes. Here, indeed, the user can either apply for job positions or join professional communities to deepen his own knowledge and expertise and be always up to date in the interested field. The primary objectives of this paper are assessing LinkedIn's usability, by using both user and expert evaluation and giving recommendations for the developer to improve this social network. This has been achieved through different steps; initially, feedbacks have been collected, via questionnaire, from direct users. Later, the usability issues, which have been underlined by users in the questionnaire, have been explored, by simulating user's problem-solving process, through Walkthrough. Finally, the overall usability of LinkedIn application has been measured by using SUS (System Usability Scale).