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In order to achieve the measurement goal of “non-destructive, high-efficiency and high accuracy” individual rape leaf area, a set of single-leaf accumulative measurement strategies using four methods including image processing method, leaf area meter method, coefficient regression method which specifies leaf length and width product, hereinafter abbreviated “L× W ”, and pattern weighing method are proposed, and carried out corresponding empirical research. The measurement accuracy analysis results showed that the image processing method, leaf area meter method, and coefficient regression method (L×W) can achieve field non-destructive and accurate measurement of rape leaf area. The image processing method has the highest measurement accuracy, followed by the leaf area meter method, the accuracy of coefficient regression method (L×W) is the lowest, and the measurement errors are 2.94%, 4.47%, and 6.01%, respectively. The measurement error caused by the difference of shooting angle is not obvious when the leaf area is measured by image processing. It is more conducive to accurate measurement to establish corresponding calibration models for different growth periods in the same method. The results of measurement efficiency analysis showed that the leaf area meter method had the highest measurement efficiency, followed by the coefficient regression method (L×W), and that of the image processing method was the lowest, whereas it is within the scope of manpower acceptable. Combined with the analysis of the number and shape of leaves in different growth periods, and scientifically dealt with the relationship between “high accuracy” and “high efficiency”, the measurement scheme was formulated that the long-petiole leaves with a width of more than 12 cm were mainly measured by image processing method, while short-petiole leaves with a width of less than 12 cm and sessile leaves were mainly measured by leaf area meter method, and all leaves were measured by the coefficient regression method (L×W), which was used to supplement the few incomplete or missed leaves, and to compare the measurement results of other methods, and the measurement scheme was corrected by the calibration model of the paper weighing method. This scheme can provide technical support for the field non-destructive measurement of individual rape leaf area. [ABSTRACT FROM AUTHOR]