The importance of monoclonal antibodies in oncology has increased drastically following the discovery of Milstein and Kohler. Since the first approval of the monoclonal antibody, i.e. Rituximab in 1997 by the FDA, there was a decline in further applications but this number has significantly increased over the last three decades for various therapeutic applications due to the lesser side effects in comparison to the traditional chemotherapy methods. Presently, numerous monoclonal antibodies have been approved and many are in queue for approval as a strong therapeutic agent for treating hematologic malignancies and solid tumors. The main target checkpoints for the monoclonal antibodies against cancer cells include EGFR, VEGF, CD and tyrosine kinase which are overexpressed in malignant cells. Other immune checkpoints like CTLA-4, PD-1 and PD-1 receptors targeted by the recently developed antibodies increase the capability of the immune system in destroying the cancerous cells. Here, in this review, the mechanism of action, uses and target points of the approved mAbs against cancer have been summarized.