Nuclear mass is one of the fundamental quantity of atomic nucleus.The total binding energy of a nucleus derived from the related mass values reflects all the interactions among the constituting nucleons.Masses of short-lived A=2Z+3 nuclei of 112Sn projectile fragments have been measured at the experimental cooler storage ring CSRe,employing the Isochronous mass spectrometry(IMS).The experiment was conducted at the Heavy Ion Research Facility in Lanzhou at the beginning of 2016.The primary beam of 112Sn35+was accumulated in the synchrotron CSRm and accelerated to 467.91 MeV/u.Secondary beam were produced by impinging the high intensity 112Sn35+beam onto a 10 mm beryllium target which was located at the entrance of the radioactive beam line RIBLL2.The projectile fragments of 112Sn emerged from the target were then transmitted,separated in flight through RIBLL2 and finally injected into CSRe.