The paper reports an association of limb-girdle muscular dystrophy and autonomous functioning thyroid nodule in two brothers and in one sister, a healthy carrier of this muscular dystrophy and with analogous thyroid pathology. It is interesting to outline the rarity of this association and the affinity of the clinical and electromyography pictures in thyrotoxic myopathy and in muscular dystrophy. In this three patients were studied: the muscular enzymes, electromyography and biopsy, HLA typing, thyroid scanning, thyroid hormone levels and TGA and TMA antibodies. However, the peculiarity of this case report may suggest the influence of genetic factors; moreover the existence of possible linkage between HLA system and association of two pathologies must be excluded, taking in account that the results of HLA types in these three Germans indicate different haplotypes.