Aim and background: The prognosis of advanced pancreatic cancer is also found to be associated with the host’s nutritional status. The prognostic nutritional index (PNI) is an emerging marker that uses serum albumin and lymphocyte count, found to be a potent prognostic measure in many malignancies. However, its efficacy in predicting clinical outcomes in pancreatic cancer is not well explored in low- and middle-income countries (LMICs), like Pakistan. Objective: To evaluate the association between PNI and clinical outcomes in patients with advanced pancreatic cancer treated at a tertiary care hospital in Pakistan between 2019 and 2023. Materials and methods: A retrospective study was conducted using patient’s record who were diagnosed with locally advanced or metastatic pancreatic cancer from Aga Khan University Hospital (AKUH). Prognostic nutritional index was calculated at diagnosis and at 12 months or last follow-up. The primary outcome was to assess the association between PNI and progression-free survival (PFS). The secondary outcome was to assess the association between PNI and type of chemotherapy drug, weight, age, stage, smoking, and alcohol intake, family history, and albumin levels at different intervals. Results: Among the included 47 patients, the association between PNI and survival was 19 months (6.44 months). Multivariable analysis showed albumin at 12 months was correlated with PNI. While the multivariable analysis of factors affecting survival revealed following significant factors, eastern cooperative oncology group (ECOG) performance, weight changes, frequency of nutritional assessment done and response evaluation. Conclusion: The PNI association with PFS further concretes the importance of this tool in clinical practices. This can lead to early identification of malnourished patients who can be treated with prompt nutritional interventions to treat pancreatic cancer-related cachexia. This is more important in context of LMIC like Pakistan where such worse outcomes add more burden on an already weak health infrastructure. However, more prospective studies with larger samples are needed to explore this associations and factors affecting PNI in more detail. Clinical significance: This study highlights the importance of nutritional assessment by utilizing PNI in patients with advanced pancreatic cancer.