This study investigates the outcomes of virtual nutritional counseling (VNC) for oncology patients during the Covid-19 pandemic. Our study evaluated the nutritional status data of cancer patients at the baseline and after VNC. An oncology dietitian evaluated the patients by video calling each patient via WhatsApp and sent an individual nutrition diet plan and recommendations via e-mail. Patient-Generated Subjective Global Assessment (PG-SGA) was used as a screening and evaluation tool to assess nutritional status. A total of 157 patients with a mean age of 55.8 ± 14.7 ( r = 19–89) were included in the study. Researchers detected at least one nutrition-related sign in 77.7% of patients. After the VNC and based on the final PG-SGA assessments, 62.2% of the patients whose baseline PG-SGA Score-B improved to Score-A, 12.5% with a baseline PG-SGA Score-C improved to Score-A and 54.2% with a baseline Score-C improved to a Score-B ( χ2 = 55,000, P < 0.001). Based on the number of VNCs, the improvement in malnutrition status following two sessions and three or more sessions was found to be 17.6% and 35.7%, respectively ( P < 0.001). Our results confirm that VNC can improve the nutritional status of cancer patients. Hence, nutritional counseling should be an integral part of oncological treatment.