A sample vessel (1, 11) for transferring and analyzing a sample with analyzer instrument, which sample vessel comprises an elongated vessel body (2, 12) for containing the sample and a hinged cap (3, 13) connected in top end area of the vessel body, and the cross-section of the vessel body (2, 12) on a transversal plane in relation to the lengthwise center axis of the vessel body the inner surface of the vessel body is rotationally asymmetrical in relation to the lengthwise center axis, wherein the sample vessel (1, 11) comprises a surface (5, 15) extending upwards from the vessel body, which surface partially surrounds the edge of the cap (3, 13), when the cap is in closed position.