The most important aspect of cancer treatment is early diagnosis. The best serum marker currently available for diagnosis of prostate cancer (CaP) is serum prostate-specific antigen (PSA). However, PSA test does not have high specificity and is not reliable for differentiating benign prostate hyperplasia, non-aggressive CaP and aggressive CaP. In the past decade, great efforts have been made in the development of novel biosensor-based strategies for detection of biomolecules and miniaturization assays for PSA. The emerging nanotechnology in recent years is expected to have a profound effect on healthcare and scientific research in the near future. Specifically, nanotechnology is foreseen to help solve one of the most challenging and longstanding problems of early cancer detection. The current mini-review summarizes the current knowledge and application of nanoarrays, nanosensors, liposomes, improved nanoparticles (dendrimers, diamondoids, gold-based nanoparticles, magnetic nanoparticles and quantum dots) and nanoelectronics in early diagnosis of prostate cancer. This mini-review highlights the most recent advances and innovative solutions in applications of nanotechnology for the detection of CaP biomarkers and early diagnosis of CaP.