To address these challenges, there is a pressing need for unconventional targeted delivery methods. Nanoparticle-based drug delivery systems offer the potential to selectively target cancer cells while minimizing damage to healthy tissues, thereby improving treatment efficacy and reducing side effects. Besides, due to their versatility and customizable nature, nanoparticles (NPs) improve treatment effectiveness by enhancing drug stability and bioavailability, thus expediting drug development. To date, several classes of NPs have been developed and investigated for targeted cancer drug delivery. Of these classes, protein nanoparticles (PNPs), namely albumin-based NPs, gained more attention, especially after nab-paclitaxel (Abraxane ® ) received FDA approval for metastatic breast cancer in 2005. This mini-review contextualizes the significance of protein-based NPs with a focus on albumin-based formulations, their clinical applications in cancer treatment, the challenges they encounter, and future possibilities for improving this technology.