More than 200 types of cancer are known today. Cancer represents the second cause of death in Europe. Statistical studies indicate that by 2035, the number of cancers in Europe could double and thus cancer would represent the first cause of death, before cardiovascular diseases. The use of metal complexes in therapy is increasing and this fact puts hope in the discovery of a new copper-based anticancer drug. The current chapter provides an overview of the types of DNA-metal complex interactions, of the antitumor mechanisms of action for the copper complexes, and presents the copper compounds in clinical study and targeted drug delivery systems based on copper in cancer treatment. PubMed, Scopus, and Web of Science databases were used to find suitable articles for this topic. The following keywords were used: cancer, Cu(II) complexes, DNA-Cu(II) complex interactions, mechanisms of action, clinical studies, and targeted drug delivery systems concerning anticancer Cu(II) complexes. Although the copper complexes have the expected antitumor activity, the problem of their toxicity is raised. Classical chemotherapy doesn’t present selectivity only for the tumor cells; therefore, the discovery of a Cu(II) complex with selectivity only for tumor cells is desirable. With the help of molecular analysis, immunotherapy, and personalized therapy, remarkable progress has been made in the treatment of cancer, but the fight against this merciless disease continues.