Background: Pain in hospitalized adults is underestimated and undervalued. The aim of this study was to evaluate pain prevalence and satisfaction with the hospital’s pain management among patients attending a tertiary university hospital. Predictor factors of pain were also studied. Methods: A prospective, cross-sectional study was carried out through a structured questionnaire given on one day to all hospitalized patients in a university hospital. Clinical data, such as personal history and analgesic treatment, were collected from medical records. Other variables related to pain (including intensity rated by the visual analogue scale as well as location and patient satisfaction measured by the numerical rating scale) were also obtained. Results: Of the 274 surveyed patients, pain prevalence was 52.9%, with an average intensity of 5.3 ± 2.8 according to VAS. The overall satisfaction was 87.2%, and 72.6% had already been prescribed at least one analgesic. Patients receiving analgesics showed higher pain intensity (VAS 3.6 ± 3.4) than those without treatment (VAS 1.1 ± 2.1) (p < 0.001). However, patients with treatment showed more satisfaction (NRS 7.8 ± 2 vs. 5.3 ± 1.4, p < 0.001). Conclusions: The prevalence of pain in hospitalized patients was high, despite the fact that patient satisfaction was also very high.