Fullerenes are fascinating symmetric carbon nanostructures with a potential to bind DNA and proteins. Computational studies were performed to investigate the interaction of fullerenes with the proteins involved in DNA mismatch repair (MMR) pathway. Significant interactions of fullerene with PMS2, RFC3 and PCNA proteins were observed. These findings suggested that fullerene interferes in the human MMR process hence the subsequent disturbance may confer a large increase in spontaneous mutability and a strong predisposition to tumor development.