A thread loop regulating arrangement is provided in a sewing machine having a reciprocated swingable needle carrying an upper thread and a loop taking arrangement including a rotatable loop taker, a bobbin carrier having a predetermined surface to receive thread loops and a bobbin positioned within the bobbin carrier. The thread loop regulating arrangement includes a relatively flat plate placed against the predetermined surface of the bobbin carrier and spaced therefrom and a downwardly extended lip for guiding the thread loop pulled off the bobbin carrier and thereby preventing the formation of undesirable stitches.