This study examines the impact of seating position and lazy glasses use on discomfort, posture, eye fatigue, and gaming experience in mobile gamers. Ten male participants aged 16–24, with normal BMI and accustomed to playing Mobile Legends for at least 2 hours daily, were involved. The study was conducted at the Ergonomics Laboratory, Department of Mechanical and Industrial Engineering, Gadjah Mada University. All subjects had normal vision verified by a Snellen card test. Devices used included an iPhone 11 Pro Max, a gaming chair, a beanbag, and lazy glasses. Discomfort was assessed using a Borg scale questionnaire, eye fatigue with the Visual Fatigue Index, and gaming experience via the Game Experience Questionnaire. Neck and joint angles were measured using inertial motion capture. Results showed that seating position and repetition significantly affected discomfort (p < 0.05), with wrist posture also influenced by chair type (p< 0.05). Lazy glasses increased eye strain (p < 0.01) and affected neck posture (p< 0.05). Repetition significantly contributed to eye fatigue (p < 0.01). It is recommended to avoid lazy glasses and prefer gaming chairs for better ergonomic comfort and experience