Background: The Neurologic Pupil Index (NPi), derived from automated pupillometry, can accurately predict poor neurological outcome in post-anoxic brain injury. The prognostic role of another index, called Pupillary Pain Index (PPI), remains unknown in this setting. Methods: Monocentric study in adult comatose cardiac arrest (CA) patients. Quantitative PPI and NPi were concomitantly recorded on day 1 and day 2 after CA. The primary study outcome was to assess the prognostic value of PPI to predict 3-month unfavourable outcome (UO, defined as Cerebral Performance Category of 3–5). Secondary outcome was the agreement between PPI and NPi to predict unfavourable outcome. Results: A total of 102 patients were included; 69 patients (68%) patients had UO. Patients with UO showed a lower NPi (4.2 [3.5-4.5] vs. 4.6 [4.3-4.7]; p Conclusions: In this study, PPI=1 on day 2 could accurately predict UO in comatose CA patients, with 100% specificity and a higher sensitivity than NPi. The agreement between PPI and NPi values was moderate.