Objective To explore the diagnostic value of Lorenz scatter plots and three-dimensional RR scatter plots in heart rate variability（HRV） analysis. Methods Selected 641 patients who underwent Holter monitor in our hospital

and collected the SDNN

Lorenz scatter plots and three-dimensional scatter plots indexes（L0

W

L0/W

L

L1

L2）.According to the SDNN value

the patients were divided into three groups: normal HRV group

HRVslight decrease group and HRV severe decrease group. We calculated the correlation between all indexes and SDNN value and tested the diagnostic value of different indexes in the reduction of HRV and its reduced degree by ROC curves.Results（1）Among the three groups

all the indexes were correlated with SDNN

and the correlation between the long axis of "sinus rhythm point" pattern（L0

L

L1

L2） and SDNN was the most significant;（2）ROC curve showed that the area under the curve（AUC） of L0was the largest in the Lorenz scatter plots and the AUC of L2in the three-dimensional scatter plots

and the best critical values were 854.60ms and 480.00ms;（3） The ROC curve of severe decreased HRV showed that the AUC of L0was 0.973 and the AUC of L2was 0.972

and the best critical values were 564.3ms and 382.5ms respectively. Conclusions The long axis of "sinus rhythm point" in Lorenz and three-dimensional scatter plots has a great diagnostic value in HRV.