The invention discloses a heart rate turbulence tendency extraction method based on a cloud model and a scatter diagram. The heart rate turbulence tendency extraction method based on the cloud model and the scatter diagram comprises the specific steps of (1) collecting HRT samples, (2) drawing the Poincare scatter diagram of RR intervals, dividing coupling points into two types of coupling points, matching the two types of the coupling points with a decelerating cloud and an accelerating cloud, and determining two ortho-state cloud curvilinear equations through a reverse-cloud generator, (3) finding critical points of two types of the coupling points, calculating linear regression slopes section by section, and storing slope vectors, (4) calculating tj_mean when changes of types continuously happen on adjacent k coupling points, and substituting the tj_mean into the two ortho-state cloud curvilinear equations to calculate the degree of membership, (5) comparing a sign yun with a subsection slope before k coupling points, comparing the sign yun and a subsection slope after the k coupling points, and classifying the k coupling points into a front subsection or a later subsection, (6) updating subsection points, calculating the linear regression slopes section by section, and updating the slope vectors, (7) mixing adjacent subsections together when the adjacent subsections are the same in sign of slopes, and repeatedly carrying out the step (6) until adjacent subsections needing to be mixed together do not exist.