Objective To explore the reference value of the quantitative index of Lorenz plot graph to evaluate heart rate variability（HRV）. Methods The adult population who visited Chongqing Three Gorges Central Hospital from November 2018 to May 2019 and whose Lorenz plots of dynamic electrocardiograms was baseball racket shapes were selected as the research objects.245 patients with no cardiovascular disease

no abnormality in dynamic electrocardiogram

and HRV within the normal range were selected as the graphical quantitative index testing group.At the same time

56 patients with abnormal HRV were selected as abnormal group. Measure the long axis（LA） and short axis（SA） of the baseball racket pattern

and calculate the area and SA/LA. Calculate the reference value range of each index in the testing group

and then compare the case where the abnormal group exceeds the reference value.Results The LA reference value of the testing group is 814-1272 ms

the SA is 130-281 ms

and the area is81081-259295 ms2. Compared with the abnormal group

the difference was statistically significant（p<0.05）. The SA/LA reference value was 0.14-0.26

compared with the abnormal group

the difference was not statistically significant（p>0.05）. In the abnormal group

46 cases（82.14%） at least one index exceeded the reference value.Conclusions The establishment of the reference value range of the quantitative index of the sinus rhythm Lorenz plot baseball bat shape graph can objectively and accurately judge the HRV

which is helpful for the clinical application of the Lorenz plot to evaluate the HRV.