Copyright © 2016 by the Endocrine Society. Context: Health-related quality of life (HRQoL) is impaired in primary hyperparathyroidism (PHPT) but instruments to specifically assess this are scarce. Objective: Validate the new disease-specific Primary Hyperparathyroidism Quality of Life (PHPQoL) questionnaire in usual clinical practice. Design: Observational, prospective, and multicenter. Setting: Public hospital ambulatory care. Patients: Patients with PHPT of both sexes, aged more than or equal to 18 years either initiated treatment for PHPT (group A) or had stable PHPT, not requiring therapy (group B). Patients in group A had at least one surgical criterion according to the 2009 Third International Workshop on Management of Asymptomatic PHPT. Intervention: Sociodemographic, clinical, and HRQoL data (PHPQol, Short Form-36, Psychological Well-Being Index, and patients' self-perceived health status) were collected. Group A underwent 4 evaluations (baseline, 3 ± 1, 6 ± 1, and 12 ± 2 months after a therapeutic intervention) and group B 2, at baseline and 1 month later to assess test-retest reliability. Results: A total of 182 patients were included (104 group A, 78 group B) with a mean age (SD) of 61.4 (12.1) years; 79.7% were women. Group A increased PHPQoL score (SD) (better HRQoL) (52 ± 23 at baseline; 62 ± 24 at 12 months; P < .001). At baseline, symptomatic patients had a lower PHPQoL score (worse) than asymptomatic ones (51 ± 21 vs 68 ± 21; P < .001). Correlations were seen between PHPQoL and Short Form-36, Psychological Well-Being Index, and self-perceived health status (P < .001). PHPQoL had good internal consistency (Cronbach's α = 0.80), test-retest reliability (group B, intraclass correlation coefficient > 0.80), and sensitivity to detect HQRoL changes over time. Conclusions: PHPQoL is a valid HRQoL measure to assess the impact of PHPT on health perception in clinical practice.