The invention discloses a GNSS satellite observation gross error elimination method applied to a reference station. The method comprises the steps of subtracting virtual observation values generated by the reference station from actual observation values of a receiver to obtain observation value residual vectors comprising a receiver clock error; sorting the observation value residual vectors andthen obtaining first difference column vectors; subtracting adjacent elements of the first difference column vectors to obtain second difference column vectors; and applying gross error determinationand identification criteria to eigen values of the first difference column vectors and the second difference column vectors and obtaining an observation value set after gross error elimination. Furthermore, the invention further discloses a GNSS satellite observation gross error elimination device, applied to the reference station, corresponding to the method. Through the GNSS satellite observation gross error elimination method and the GNSS satellite observation gross error elimination device, effective elimination of observation gross errors of the reference station is achieved, and the reliability of high-precision relative positioning is enhanced.