This research is aimed at analyzing the quality of service (QoS) of 5Ghz wireless networks on Telkom University Landmark Tower (TULT) Building (Telkom University landmark tower). In this research, an interview was conducted with Mr. Sakti Putro Wisetyo as the IT infrastructure section at PUTI to obtain information about wireless network information at Telkom university landmark tower such as network infrastructure, network devices, network device placement, 5 GHz wireless deployment, and challenges in managing network infrastructure. This research uses the PPDIOO method in the implementation of wireless internet networks and as a consideration in developing wireless Internet networks. The results of this research are that the main cause of interference is due to over coverage, channel repetition, and wrong access point placement, where the access point type RG-AP130(W2) V2 is an access point that has a wall mount installed and not a ceiling mount so any of these problems can cause co-channel interference. This research will be useful in improving the efficiency of its business processes so that students and lecturers can be more productive in academic activities.