Fakhar ud Din,1,* Waqar Aman,2,* Izhar Ullah,3 Omer Salman Qureshi,4 Omer Mustapha,5 Shumaila Shafique,6 Alam Zeb7 1Department of Pharmacy, Quaid-i-Azam University, Islamabad, 2Department of Pharmacy, Kohat University of Science and Technology, Kohat, 3Department of Health and Medical Sciences, University of Poonch, Rawalakot, Azad Kashmir, 4Faculty of Pharmacy, University of Lahore, Lahore, 5Faculty of Pharmacy, Ziauddin University, Karachi, 6Department of Pharmaceutics, Faculty of Pharmaceutical Sciences, Dow University of Health Sciences, Karachi, 7Riphah Institute of Pharmaceutical Sciences, Riphah International University, Islamabad, Pakistan *These authors contributed equally to this work Abstract: Nanotechnology has recently gained increased attention for its capability to effectively diagnose and treat various tumors. Nanocarriers have been used to circumvent the problems associated with conventional antitumor drug delivery systems, including their nonspecificity, severe side effects, burst release and damaging the normal cells. Nanocarriers improve the bioavailability and therapeutic efficiency of antitumor drugs, while providing preferential accumulation at the target site. A number of nanocarriers have been developed; however, only a few of them are clinically approved for the delivery of antitumor drugs for their intended actions at the targeted sites. The present review is divided into three main parts: first part presents introduction of various nanocarriers and their relevance in the delivery of anticancer drugs, second part encompasses targeting mechanisms and surface functionalization on nanocarriers and third part covers the description of selected tumors, including breast, lungs, colorectal and pancreatic tumors, and applications of relative nanocarriers in these tumors. This review increases the understanding of tumor treatment with the promising use of nanotechnology. Keywords: nanocarriers, drug delivery, solid lipid nanoparticles, liposomes, polymeric nanoparticles, dendrimers, breast tumor, lungs tumor, colorectal tumor, prostate tumor