The present invention provides a quinazoline compound shown in formula (I), or pharmaceutically acceptable salt thereof. R1, R2 and R7 are independently and respectively selected from hydrogen, C1-6 alkyl, C1-6 alkoxy, halogenate C1-6 alkyl, halogenate C1-6 alkoxy, hydroxyl C1-6 alkyl, hydroxyl C1-6 alkoxy, C1-6 alkoxy C1-6 alkoxy, C3-8 cycloalkyloxy, optional aryl or heteroaryl substituted by R6, nitryl, amino, C1-6 alkylamino, and di(C1-6 alkyl)amino; it comprises at least one C3-8 heterocycloalkyloxy selected from N, O, S heteroatoms; Z is -NR4-, C(R5)2, S or -O-, R4 being hydrogen or C1-3 alkyl, and R5 being selected from hydrogen or C1-3 alkyl; R3 is selected from hydrogen, halogen, C1-6 alkyl, C1-6 alkoxy or halogenate C1-6 alkyl; R6 is selected from hydrogen, C1-3 alkyl, hydroxyl, halogen, C1-3 alkoxy; and n is 0 to 5. The present invention further provides a preparation method of the compound shown in formula (I) or the pharmaceutically acceptable salt and pharmaceutical usage thereof, which can be used as medicines or lead compounds for curing diseases such as tumour and cancer related to protein tyrosine kinase.