A data output apparatus and method in a global input and output (GIO) line transmits data via the GIO line. This data output apparatus includes a read driver driven responsive to an input of read data for inverting and amplifying the data to output inverted and amplified data onto the GIO line, a GIO termination unit driven responsive to a termination signal for rising or falling a voltage level on the GIO line by a preset level, prior to driving the data onto the GIO line by the read driver, and a receiver driven responsive to the read data transmitted through the GIO line for inverting and amplifying the read data to provide inverted and amplified data. This data output apparatus can enable a high rate data transmission by decreasing a swing width of data transmitted via the GIO line and also reduce a coupling noise on adjacent lines.