Sodium (Na⁺) and potassium (K⁺) are essential electrolytes involved in various biological processes, including tumor cell proliferation, migration, and metabolism. However, the role of serum sodium and potassium levels in patients with ocular tumors remains unclear. This analytical observational study employed a cross-sectional design involving 60 subjects, consisting of 30 patients with ocular tumors and 30 healthy controls. Serum sodium and potassium levels were measured using the Ion Selective Electrode (ISE) method. Differences between groups were analyzed using the Mann-Whitney test with a significance level of p<0.05. Most ocular tumors were benign, with squamous papilloma being the most common histopathological diagnosis (16.7%). The mean serum sodium level was higher in the ocular tumor group than in the control group (146 ± 8.42 mmol/L vs 143.13 ± 2.97 mmol/L); however, the difference was not statistically significant (p=0.061). Mean serum potassium levels were comparable between the ocular tumor and control groups (4.22 ± 0.53 mmol/L vs 4.30 ± 0.64 mmol/L), with no statistically significant difference (p=0.700). Although a trend toward higher serum sodium levels was observed in the ocular tumor group, serum sodium and potassium levels cannot currently be considered diagnostic biomarkers for ocular tumors.