The study is about the impact of quarterly financial result announcement on stock price of selected plastic company. The objective of the study is to investigate before and after impact of Earnings announcements on the selected plastic stocks. The four plastic companies Quarterly result report and share price data for last five years (2011-12 to 2015-16) have been used for study. The paired sample t test is used to compare the prices of stocks before announcement and after announcement of quarterly results by companies. The Researchers found that out of 79 quarter in total of five years, 31 quarter has shown negative effect, it means after the announcement of results, share price goes down. The positive effect found in 18 quarter, which suggest that, after the announcement of quarterly result, the share price shows positive trend. Whereas, in remaining 30 quarters there is no effect, it means before and after announcement, the price remains the same. So it is found that, quarterly result has a mix results on companys share price. It can be said that, there are other factors also which affects share price in Indian Market.