A stamp assembly comprising: a bracket having a top; and a bracket hole formed through the top of the bracket in a latitudinal direction of the bracket; a stamping member mounted in the bracket below the bracket hole, and capable of being moved in a longitudinal direction relative to the bracket and being rotated; an ink cartridge mounted in the bracket hole of the bracket; a spring mounted in the bracket and having a top end; and a bottom end opposite to the top end of the spring and pressed against the top of the bracket; a housing (5,5A) mounted around the bracket, capable of being moved in a longitudinal direction relative to the bracket, connected with the stamping member, and having a shell (50,50A) mounted around the bracket, capable of being moved in a longitudinal direction relative to the bracket, and having a front side; a rear side opposite to the front side of the shell (50,50A); and two opposite flanks; a through hole (52,52A) formed through the front side of the shell (50,50A); and a shell hole formed through a bottom of the rear side of the shell (50,50A) such that a bottom surface of the rear side of the shell (50,50A) is located above a bottom surface of the front side of the shell (50,50A), wherein the ink cartridge is located between the shell hole and the through hole (52,52A), characterized in that the stamp assembly further comprises a pushing device mounted on the front side of the shell (50,50A) and having a pushed member (60,60A) slidably mounted in the through hole (52,52A) of the housing (5,5A) and capable of pushing the ink cartridge out of the bracket. a bracket having a top; and a bracket hole formed through the top of the bracket in a latitudinal direction of the bracket; a top; and a bracket hole formed through the top of the bracket in a latitudinal direction of the bracket; a stamping member mounted in the bracket below the bracket hole, and capable of being moved in a longitudinal direction relative to the bracket and being rotated; an ink cartridge mounted in the bracket hole of the bracket; a spring mounted in the bracket and having a top end; and a bottom end opposite to the top end of the spring and pressed against the top of the bracket; a top end; and a bottom end opposite to the top end of the spring and pressed against the top of the bracket; a housing (5,5A) mounted around the bracket, capable of being moved in a longitudinal direction relative to the bracket, connected with the stamping member, and having a shell (50,50A) mounted around the bracket, capable of being moved in a longitudinal direction relative to the bracket, and having a front side; a rear side opposite to the front side of the shell (50,50A); and two opposite flanks; a through hole (52,52A) formed through the front side of the shell (50,50A); and a shell hole formed through a bottom of the rear side of the shell (50,50A) such that a bottom surface of the rear side of the shell (50,50A) is located above a bottom surface of the front side of the shell (50,50A), wherein the ink cartridge is located between the shell hole and the through hole (52,52A), characterized in that the stamp assembly further comprises a pushing device mounted on the front side of the shell (50,50A) and having a pushed member (60,60A) slidably mounted in the through hole (52,52A) of the housing (5,5A) and capable of pushing the ink cartridge out of the bracket. a shell (50,50A) mounted around the bracket, capable of being moved in a longitudinal direction relative to the bracket, and having a front side; a rear side opposite to the front side of the shell (50,50A); and two opposite flanks; a front side; a rear side opposite to the front side of the shell (50,50A); and two opposite flanks; a through hole (52,52A) formed through the front side of the shell (50,50A); and a shell hole formed through a bottom of the rear side of the shell (50,50A) such that a bottom surface of the rear side of the shell (50,50A) is located above a bottom surface of the front side of the shell (50,50A), wherein the ink cartridge is located between the shell hole and the through hole (52,52A), characterized in that the stamp assembly further comprises a pushing device mounted on the front side of the shell (50,50A) and having a pushed member (60,60A) slidably mounted in the through hole (52,52A) of the housing (5,5A) and capable of pushing the ink cartridge out of the bracket. a pushed member (60,60A) slidably mounted in the through hole (52,52A) of the housing (5,5A) and capable of pushing the ink cartridge out of the bracket.