β-Blockers have been one of the most widely used and versatile drugs for the past half a century. A new potential for their use as anti-cancer drugs has emerged in the past few years. Various retrospective case control studies have been suggestive that use of β-blockers before the diagnosis of cancer could have preventive and protective effects against non-small cell lung carcinoma, melanoma, and breast, pancreatic and prostate cancers. Experimental and clinical observations are still inconclusive with some inconsistent findings. However, indications are pointing toward a positive role of some β-blockers against certain forms of cancers. This mini review is an effort to present the up to date published results of case-control studies and experimental findings.