Sentiment analysis is the task in Natural Language Processing to determine whether the writer’s attitude about a topic is positive, negative or neutral. Nowadays, a lot of companies use sentiment analysis of the opinion on the social media sites to extract the valuable information. In this project I have performed the sentiment analysis of Android app reviews by using Naïve Bayes classification algorithm. I have taken the dataset of positive and negative reviews for training purpose. The system takes reviews and displays the result in webpage classifying positive reviews and negative reviews in two groups. The accuracy of 78.22% was obtained while testing the classification algorithm using test dataset.