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Purpose:To test the accuracy and reliability of implementing volumetric modulated arc therapy(VMAT)with Axesse linear accelerator.Methods:The functional performance of VMAT was tested in a stepwise manner,from component test to whole process test.Firstly,the consistence of dosimetric output was tested for fixed gantry and arc therapy.Secondly,the positioning accuracy of dynamic multileaf collimator(DMLC)during arc therapy was examined.Then,the ability of controlling the variable dose-rate and gantry speed,controlling the variable MLC speed and dose-rate was studied.Finally,the resumption of interrupted treatment and patient specific dosimetric verification was also investigated.Results:The dosimetric output was within 1.0%for arc therapy with DMLC compared with fixed gantry irradiation.The MLC position error of 0.5 mm can be easily visualized using iViewGT 3.40 of Axesse.The patterns obtained of the picket fence test for fixed gantry and arc therapy showed the MLC position error is less than 1 mm.The normalized doses were within 2.0%for the strips with different dose-rate,gantry speed and dose-rate,MLC speed combinations in VMAT.Beam interruption,door interlock,emergency off could be properly handled,and the treatment could be resumed correctly,with a correct record of the MU delivered in Axesse.The pass rates of gamma value were 96.52%,95.72%and 98.83%for the cervical cancer,prostate cancer and breast cancer patients,respectively,with the criteria of 3 mm/3%for distance to agreement and dose difference.Conclusions:Dynamic MLC movement,variable dose-rates and gantry speeds can be accurately and reliably controlled in Axesse during VMAT.Axesse has been shown to be suitable for VMAT delivery.