Background Cancer patients have an increased risk of a severe COVID-19 infection with higher mortality rate. This study aimed to analyze the levels of anti-SARS-CoV-2 S-RBD IgG and NAB among cancer patients who were vaccinated with COVID-19 vaccines, either with BNT162b2, mRNA-1273, AZD1222/ChAdOx1nCoV-19, or Coronavac/BBIBP-CorV vaccines. Method A cross-sectional study was conducted among subjects with either solid or hematological cancers who had received two doses of either mRNA or non-mRNA vaccines within 6 months. The levels of anti-SARS-CoV-2 S-RBD IgG and NAb were analyzed using the Mindray Immunoassay Analyzer CL-900i. Statistical analysis was conducted using mean comparison and regression analysis. Result The mRNA-1273 vaccine had the highest median levels of S-RBD IgG and NAb, followed by BNT162b, ChAdOx1nCoV-19, and BBIBP-CorV/Coronavac. The levels of S-RBD IgG and NAb in subjects vaccinated with mRNA vaccines were significantly higher than those of non-mRNA vaccines when grouped based on their characteristics, including age, type of cancer, chemotherapy regimen, and comorbidity (p<0.05). Furthermore, the S-RBD IgG and NAb levels between the subjects vaccinated with non-mRNA vaccines and the subjects vaccinated with mRNA vaccines were significantly different (p<0.05). However, there was no significant difference between the same types of vaccines. This study demonstrated a very strong correlation between the level of S-RBD IgG and the level of NAb (R = 0.962; p<0.001). The level of anti-SARS-CoV-2 S-RBD IgG was consistently higher compared to the level of NAb. Conclusions Generally, mRNA vaccines produced significantly higher anti-SARS-CoV-2 S-RBD IgG and NAb levels than non-mRNA vaccines in cancer subjects.