Fruits, vegetables, spices, herbs and/or beverages are typical foods containing various phytochemicals that have been used for prevention and treatment of a variety of human ailments since time immemorial. Nowadays, a large number of individuals are motivating towards the use of phytochemicals inorder to prevent or treat chronic diseases. Recent research efforts have been greatly emphasized on the recognition of naturally occurring plant derived substances that are capable of inhibiting, retarding or reversing the development of cancer. Several epidemiological annotations and a number of laboratory studies have indicated cancer chemopreventive and anti-carcinogenic potential of plant derived agents that have been traditionally used for treatment of varied human disorders in different parts of the globe. Molecular mechanisms which are involved for eliciting the effects of phytochemicals in cancerous cells are noticed in a range of experimental systems. This has opened up new avenue for researchers working in the field of chemoprevention and merits further scrutiny to establish the role of phytochemicals in prevention of fatal human diseases like cancer.