To provide a method for handing a sample test tube and an image analyzing unit for laboratory sample test tubes stored in a rack.

An image analyzing unit determines a parameter for a shape of at least one sample test tube stored in a primary rack by image analysis. An identification/allocation unit compares the parameter for the determined shape with a predetermined shape reference, identifies whether or not the shape of the sample test tube satisfies the predetermined shape reference for each sample test tube, classifies the sample test tube to "system adapted" when the shape satisfies the shape reference, and if the shape does not satisfy the shape reference, classifies the sample test tube to "non-system adapted". Each sample test tube determined as "system adapted" is shifted to further processing, and each sample test tube determined as "non-system adapted" is shifted to error processing.