The invention discloses a measurement method for a field rice leaf rolling degree based on machine vision. The method comprises the steps that a rice RGB image is shot, the perimeter to area ratio andthe plant occupation ratio of rice population are extracted by using an image treatment technology and used as digital leaf rolling values of the rice population, and the defects can be overcome thatin the prior art, an artificial detection means is high in subjectivity and can only conduct grading and scoring on rice leaf rolling; continuous and quantitative measurement of the rice leaf rollingdegree is achieved, and the method can be conveniently popularized and applied to measurement work of the leaf rolling degree of other crops. Compared with the prior art, the measurement method for the field rice leaf rolling degree based on machine vision has the technical advantages of being capable of quantitatively measuring the rice leaf rolling degree, lossless and easy to operate.