Driving method and circuit and OLED display device

The invention provides a driving method and circuit and an OLED (organic light-emitting diode) display device. The driving method comprises the following steps: determining the length of a power line between a pixel unit connected with a scanned grid line and a power source end for providing power voltage for the pixel unit; calculating a data voltage correction value according to the length; and adjusting a Gamma curve to correct data voltage of a data line connected with the pixel unit according to the data voltage correction value. The problem of poor display brightness uniformity in the prior art is solved. 本发明提供了种驱动方法、电路和OLED(有机发光二极管)显示装置。所述驱动方法包括：确定与被扫描的栅线连接的像素单元和为所述像素单元提供电源电压的电源端之间的电源线的长度；根据所述长度计算数据电压修正值；调节Gamma曲线，以根据所述数据电压修正值修正与所述像素单元连接的数据线上的数据电压。本发明解决现有技术中显示亮度均性差的问题。