The present invention relates to conjugates of hydroxyalkyl starch, preferably hydroxyethyl starch, and a protein, wherein these conjugates are formed by a reductive amination reaction between at least one aldehyde group or keto group or hemiacetal group of the hydroxyalkyl starch or of a derivative of the hydroxyalkyl starch, and at least one amino group of the protein, so that the hydroxyalkyl starch or the derivative thereof is covalently linked to the protein via an azomethine linkage or a amino linkage. The present invention also relates to the method of producing these conjugates and specific uses of the conjugates.
