An image sensor comprises a row driver, a first row line which is connected to the row driver, first to fourth pixels connected to the first row line, first to fourth column lines connected to the first to fourth pixels and configured to receive respective first to fourth output signals from the first to fourth pixels, a boosting circuit connected to the first to fourth column lines, a second row line connected to the boosting circuit, first and second boosting drivers connected, respectively, to first and second terminals of the second row line. The boosting circuit may adjust voltage of the first and second output signals based on a first boosting enable signal received from the first boosting driver and may adjust a voltage of the third and fourth output signals based on a second boosting enable signal received from the second boosting driver.