Background: Scaling of the scalp is a feature of a number of clinical disorders including dandruff, seborrheic dermatitis and psoriasis. Dandruff may be caused by several different factors including overgrowth of Malassezia species. There is a debate around the role of Malassezia species in psoriasis. Several reports have associated these lipophilic yeasts with the development of skin lesions in both dandruff and psoriasis. Objectives: This work is conducted in order to clarify the role of Malassezia species in dandruff whether an aetiological role or secondary to accumulation of scales in comparison to psoraitic scales of the scalp. Patients and Methods: Our work was conducted on 20 patients complaining of dandruff, not proceeding to seborrheic dermatitis and 20 patients complaining of scalp psoriasis. The patients were instructed to apply bland shampoo and topical hydrocortisone cream 1% for two weeks. The patients were clinically and mycologically assessed before and after the treatment period. Results: There was a positive correlation between the yeast density in both groups and the amount of scales, regardless of the aetiology of the disease. Also a significant reduction in the density of scales, associated with significant decrease in the density of Malassezia yeast without the need for antifungal agents, was noted. Conclusion: The results obtained in our study form a strong backbone for the hypothesis that Malassezia species play no primary aetiological role in either dandruff or psoriasis. Their population increases secondary to the increase in the habitat (scales), and can be reduced by removing these scales, regardless of the treatment used.