The authors describe a clinical case of a 58 years old individual with hypertimic temperament, without pathological antecedents and previous psychiatric history and that initiated compatible syntomatology with a first maniac episode. Alterations of the behavior with heteroagressivity in relation to his wife, hypersexuality, disturbance of sleep with almost total insomnia, euphoria, rapid thinking, rapid and senseless speech, revealing delirious ideas of grandiosity and hypergraphia could be observed. A tracing for a secondary aetiology of mania was carried out, having been concluded to be a bipolar disorder of delayed onset. Currently the patient is stabilized with sodium valproate 1500mg/day and risperidone 1mg/day and is regulary observed in a psychiatric consultation. This case alert to the possibility of late onset of a bipolar disorder, however it is always necessary to carry out complementary study to exclude secondary causes of mania.