Stroke-associated pneumonia (SAP) is a common complication of acute ischemic stroke (AIS). This single-center retrospective observational study aimed to identify factors associated with SAP and predictors of poor outcomes in hospitalized patients with AIS. The study included patients admitted to Chumphon Khet Udomsakdi Hospital in Thailand within 7 days of the onset of AIS between July 2019 and July 2020. The patients were divided according to whether they were diagnosed with SAP during hospitalization into a pneumonia group and a non-pneumonia (control) group. Factors associated with SAP were identified. After 3 months, the patients with AIS were divided into those with a poor outcome (modified Rankin scale [mRS] score ≥4) and those with a non-poor outcome (mRS score <4). Factors associated with a poor outcome were sought. During the study period, 342 patients (mean age 65 years, 61% men) were admitted with AIS, of whom 54 (15.8%) developed SAP. Multivariate analysis identified a failed water-swallowing test (WST; adjusted odds ratio [aOR] 87.48, 95% confidence interval [CI] 21.00–364.51, p<0.001), endotracheal intubation with invasive mechanical ventilation (aOR 12.38, 95% CI 2.44–101.35, p = 0.001), and a retained Foley catheter (aOR 5.67, 95% CI 2.03–15.83, p = 0.001) to be associated with SAP. Of the 342 patients, 112 (32.7%) had a poor outcome at 3 months, predictors of which included having hypertension as a comorbidity (aOR 2.87, 95% CI 1.18–6.98, p = 0.020), a pre-stroke mRS score ≥2 (aOR 4.53, 95% CI 1.50–12.72, p = 0.007), an initial Barthel Index score <40 (aOR 3.35, 95% CI 1.57–7.16, p = 0.002), a failed WST (aOR 5.04, 95% CI 2.00–12.74, p = 0.001), and brain edema (aOR 20.67, 95% CI 2.10–203.26, p = 0.009). This study emphasized the association of SAP with a failed WST, endotracheal intubation with invasive mechanical ventilation, and a retained Foley catheter but also identified hypertension, a pre-stroke mRS score ≥2, an initial BI score <40, a failed WST, and brain edema as predictors of a poor outcome for patients 3 months after AIS.