This study examined long-term relationships between oil prices from OPEC reference basket and stock prices of 12 oil and gas companies listed on the Karachi Stock Exchange as well as with their respective trade volumes. Since oil is the major input for oil companies so they are bound to be susceptible to fluctuations in the value of international crude. This study was conducted to estimate cointegration between oil price volatility and stock prices as well as oil price and trading volume of oil companies trading on KSE and to identify the long run behavior and to adjust the short term disequilibrium with other periods of the long run.