Background: Pain is often inadequately evaluated and treated in sub-Saharan Africa (SSA). Objective: We sought to assess pain levels and pain treatment in 400 hospitalized patients at a national referral hospital in western Kenya, and to identify factors associated with pain and pain treatment. Design: Using face-validated Kiswahili versions of two single-item pain assessment tools, the Numerical Rating Scale (NRS) and the Faces Pain Scale-Revised (FPS-R), we determined patients' pain levels. Additional data collected included patient demographics, prescribed analgesics, and administered analgesics. We calculated mean pain ratings and pain management index (PMI) scores. Results: Averaged between the NRS and FPS-R, 80.5% of patients endorsed a nonzero level of pain and 30% of patients reported moderate to severe pain. Older patients, patients with HIV, and cancer patients had higher pain ratings. Sixty-six percent of patients had been prescribed analgesics at some point during their hospitalization, the majority of which were nonopioids. A majority of patients (66%) had undertreated pain (negative scores on the PMI). Conclusion: This study shows that hospitalized patients in Kenya are experiencing pain and that this pain is often undertreated.