This paper deals mainly with the precursory features of apparent resistivity and acoustic emission of the large scale granite specimen during the process of slowly rupturing due to a dilatancy source. The results show that not only the long tendency of anomaly and shortterm anomaly in resistivity were observed before the main rupture occurrence, but the precursors associated with rupture were observed clearly as well, i.e. a sudden change in apparent resistivity several hours prior to the main rupture occurrence. The precursor in acoustic emission was also recorded in the experiment, the starting time, however, is later than that in apparent resistivity. And there are respective distinctions in the acoustic emission during the initial microrupture and the final main rupture.