An analysis cartridge comprising: a sealing film , a cartridge having a first surface and a second surface , and a first cover covering the first surface , said cover having a through hole , said cartridge having: - an opening , - a liquid storage box with an unvented liquid storage chamber disposed therein for storing a diluent (L), said liquid storage box having a liquid through-hole , - a liquid channel , and - at least one reaction chamber for storing a reactive substance , wherein the liquid channel interconnects the at least one reaction chamber with the unvented liquid storage chamber via said liquid through hole ; wherein the sealing film is configured to pass through the through hole of the first cover and through the opening of the cartridge ; wherein a first terminal of the sealing film is configured to seal the unvented liquid storage chamber by sealing the through-hole of the liquid storage box to avoid diluent flowing out when analysis is not yet performed, and a second terminal of the sealing film is configured to be pulled by an operator to expose the liquid through hole and the unvented storage chamber when analysis is performed; wherein the sealing film penetrates the opening and the through hole by way of reversely bending the sealing film when analysis is not yet performed; and wherein, when analysis is not yet performed, the first terminal of the sealing film has a folded portion which overlaps the through hole , and the second terminal is configured to pass through the through hole of the first cover and through the opening , such to be upward extended out of the cartridge . a sealing film , a cartridge having a first surface and a second surface , and a first cover covering the first surface , said cover having a through hole , said cartridge having: - an opening , - a liquid storage box with an unvented liquid storage chamber disposed therein for storing a diluent (L), said liquid storage box having a liquid through-hole , - a liquid channel , and - at least one reaction chamber for storing a reactive substance , - an opening , - a liquid storage box with an unvented liquid storage chamber disposed therein for storing a diluent (L), said liquid storage box having a liquid through-hole , - a liquid channel , and - at least one reaction chamber for storing a reactive substance , wherein the liquid channel interconnects the at least one reaction chamber with the unvented liquid storage chamber via said liquid through hole ; wherein the sealing film is configured to pass through the through hole of the first cover and through the opening of the cartridge ; wherein a first terminal of the sealing film is configured to seal the unvented liquid storage chamber by sealing the through-hole of the liquid storage box to avoid diluent flowing out when analysis is not yet performed, and a second terminal of the sealing film is configured to be pulled by an operator to expose the liquid through hole and the unvented storage chamber when analysis is performed; wherein the sealing film penetrates the opening and the through hole by way of reversely bending the sealing film when analysis is not yet performed; and wherein, when analysis is not yet performed, the first terminal of the sealing film has a folded portion which overlaps the through hole , and the second terminal is configured to pass through the through hole of the first cover and through the opening , such to be upward extended out of the cartridge . <EOS>