Dysferlinopathies encompass a large variety of neuromuscular disease characterized by the absence of dysferlin in skeletal muscle and an autosomal recessive mode of inheritance. Dysferlin is a large protein involved in membrane repair and vesicle trafficking and interacts probably with important immunological pathways. Here we present a case of a patient who presented with bilateral proximal pure motor muscle weakness of 18 months duration followed by right upper limb proximal weakness and atrophy of distal half of biceps muscle. No significant family history was evident. Patient had grossly elevated CPK and EMG revealed features of polymyositis. Clinical examination revealed bilateral ‘diamond on quadriceps‘ sign, specific for dysferlinopathy. Subsequently genetic analysis revealed heterozygous mutation in dysferlin gene.