A method for measuring remaining hydrogen capacity of hydrogen storage canister by applying tag information, wherein at least one hydrogen storage canister is provided for supplying hydrogen to support a reaction in an application device, the hydrogen storage canister comprising an information identification tag, which stores at least one record of tag information indicating a hydrogen storage quantity of the hydrogen storage canister, the method comprising the following steps: (a) reading the tag information from the information identification tag; (b) detecting a hydrogen consumption quantity supplied from the hydrogen storage canister; (c) subtracting the hydrogen consumption quantity from the hydrogen storage quantity to calculate a residual hydrogen quantity; detecting a hydrogen storage pressure of the hydrogen storage canister; and (d) updating the tag information of the information identification tag by replacing the tag information with the residual hydrogen quantity so calculated, characterized in that is further comprises after step the following steps: determining if the hydrogen storage pressure is lower than a preset hydrogen pressure threshold; determining if the residual hydrogen quantity is lower than a preset hydrogen residue threshold, when the hydrogen storage pressure is lower than the hydrogen pressure threshold, for determination of correctness of the residual hydrogen quantity; and issuing an alarm when the residual hydrogen quantity is higher than the hydrogen residue threshold but the hydrogen storage pressure is lower than the hydrogen pressure threshold. (a) reading the tag information from the information identification tag; (b) detecting a hydrogen consumption quantity supplied from the hydrogen storage canister; (c) subtracting the hydrogen consumption quantity from the hydrogen storage quantity to calculate a residual hydrogen quantity; detecting a hydrogen storage pressure of the hydrogen storage canister; and (d) updating the tag information of the information identification tag by replacing the tag information with the residual hydrogen quantity so calculated, characterized in that is further comprises after step the following steps: determining if the hydrogen storage pressure is lower than a preset hydrogen pressure threshold; determining if the residual hydrogen quantity is lower than a preset hydrogen residue threshold, when the hydrogen storage pressure is lower than the hydrogen pressure threshold, for determination of correctness of the residual hydrogen quantity; and issuing an alarm when the residual hydrogen quantity is higher than the hydrogen residue threshold but the hydrogen storage pressure is lower than the hydrogen pressure threshold. determining if the hydrogen storage pressure is lower than a preset hydrogen pressure threshold; determining if the residual hydrogen quantity is lower than a preset hydrogen residue threshold, when the hydrogen storage pressure is lower than the hydrogen pressure threshold, for determination of correctness of the residual hydrogen quantity; and issuing an alarm when the residual hydrogen quantity is higher than the hydrogen residue threshold but the hydrogen storage pressure is lower than the hydrogen pressure threshold.