Recent observations show evidence that high-z (z ~ 2 − 3) early-type galaxies (ETGs) are more compact than those with comparable mass at z ~ 0 (e.g. Trujillo et al. 2007; Buitrago et al. 2008). Such a size evolution is most likely explained by the ‘dry merger scenario’. However, previous studies based on this scenario are not able to consistently explain both the properties of the high-z compact massive ETGs and the local ETGs (Nipoti et al. 2009). We investigate the effect of multiple sequential minor mergers on the size evolution of the compact massive ETGs.