DNA vaccines have a wide range of applications, with several potential advantages compared to other vaccine technologies for diseases. No DNA vaccine has yet been licensed in humans; however, a lot of effort has been made to enhance their potential as human vaccines and therapeutics. Finding an effective adjuvant is a strategy to improve the efficacy of DNA vaccines. We recently identified a fungal immunomodulatory protein Ling Zhi-8 (LZ-8) with stimulatory activity on dendritic cells (DCs) that significantly increases the efficacy of a cancer DNA vaccine in a preclinical tumor model, suggesting that LZ-8 may be a good candidate adjuvant for vaccine development. Here we discuss the possibility for applying LZ-8 to a cancer DNA vaccine for humans.