Nowadays soy is one of the world's most important vegetable, protein and oil source, and therefore it has a significant importance in nutrition. As a result of the accelerating population growth, it is anticipated that even more scientific knowledge of our crops will be needed, because with the help of this knowledge we could calculate growth, development and yield, too. Our work includes the measurement results of 15 plants and 603 leaves. The leaf areas were obtained with two different methods (manual and segmentation). I examined the applicability of these methods and - based on the measured data - examined the difference between each letter level. I settled them into categories and then the categories were presented in a box-plot diagram. I also presented how many leaves can be found depending on their size and the distribution of the leaf areas.