Tyrosine kinases are very important group of enzymes which regulate signalling pathways in the cell that control, cell growth, differentiation, apoptosis and large number of other biochemical processes. Overexpression of tyrosine kinases leads to abnormal cell proliferation and is associated with tumour invasion, metastasis and angiogenesis. A lot of tyrosine kinases have been used as targets in the screening for anti-tumour drugs. The inhibitors of these enzymes compete with ATP for the ATP-binding site, thereby significantly reducing phosphorylation of tyrosine kinases resulting in inhibition of, cancer cell proliferation. Great progress has been made recently in cancer treatment with tyrosine kinase inhibitors. This thesis describes the role of tyrosine kinases in cancer biology, gives examples of clinically approved, tyrosine kinase inhibitors as anti-cancer drugs and discusses, challenges and limitations of tyrosine kinase inhibitors in cancer treatment.