(1) Background: Clinical aspects like sex, age, Karnofsky Performance Scale (KPS) and psychosocial distress can affect the health-related quality of life (HR-QoL) and treatment satisfaction of patients with malignant isocitrate dehydrogenase wild-type (IDHwt) gliomas and caregivers. (2) Methods: We prospectively investigated the HR-QoL and patient/caregiver treatment satisfaction in a cross-sectional study with univariable and multiple regression analyses. Questionnaires were applied to investigate the HR-QoL (EORTC QLQ-C30, QLQ-BN20) and treatment satisfaction (EORTC PATSAT-C33). (3) Results: A cohort of 61 patients was investigated. A higher KPS was significantly associated with a better HR-QoL regarding the functional scales of the EORTC QLQ-C30 (p < 0.004) and a lower symptom burden regarding the EORTC QLQ-BN20 (p < 0.001). The patient treatment satisfaction was significantly poorer in the patients older than 60 years in the domain of family involvement (p = 0.010). None of the investigated aspects showed a significant impact on the treatment satisfaction of caregivers. (4) Conclusions: We demonstrated that in patients with IDHwt gliomas, the KPS was the most important predictor for a better HR-QoL in functional domains. Data on the HR-QoL and treatment satisfaction in patients with IDHwt gliomas and their caregivers are rare; therefore, further efforts should be made to improve supportive care in this highly distressed cohort.