Liposomal amphotericin B (L-AMB) causes renal dysfunction and hypokalemia, but little is known about the relationship between serum electrolyte levels before or after administration and renal dysfunction. The changes in serum electrolyte levels before and after administration in patients with L-AMB-induced renal dysfunction were examined. This study included 87 patients administered L-AMB at Kindai University Nara Hospital. The number of patients with G1 (serum creatinine (Scr) levels (mg/dL) > 1.07–1.605 in male and > 0.79–1.185 in female) and G2 (Scr level > 1.605–3.21 in male and > 1.185–2.37 in female) was 25 (28.7%) and 14 (16.1%), respectively. Multivariable logistic regression analysis revealed the onset of G2 was significantly associated with baseline estimated glomerular filtration rate (eGFR), odds ratio (OR): 0.99, 95% confidential interval (95% CI): 0.95–1.02 and, baseline serum potassium levels, OR: 3.50, 95% CI: 1.16–12.06. Serum potassium levels were significantly higher in the G2 group than in the G0 group (Scr levels < 1.07 in male and < 0.79 in female) during the study period. These results indicated the changes in serum potassium levels are associated with renal dysfunction. Monitoring of serum potassium levels before and after administration may contribute to the evaluation of renal dysfunction in patients receiving L-AMB.