A multi-primary-color liquid crystal panel driver (100) according to the present invention includes: a multi-primary-color converter (110) which performs a multi-primary-color conversion to convert the grayscale levels of an input video signal in each of a plurality of vertical scanning periods into grayscale levels of four or more primary colors; and an overdrive circuit (120) which sets, based on the grayscale levels that have been subjected to the multi-primary-color conversion in one vertical scanning period and on the grayscale levels that have been subjected to the multi-primary-color conversion in another vertical scanning period that is earlier than the one vertical scanning period by at least one period, the grayscale levels of the four or more primary colors in that one vertical scanning period. The present invention provides a multi-primary-color liquid crystal panel that can improve the display quality even when the input video signal has varying grayscale levels.