Over the last 13 years 2745 patients from all over Greece suspected to have a lysosomal storage disorder were referred to the Institute of Child Health. 1581 of those were suspected of having a mucopolysaccharidosis (MPS). 94 cases (3.42% of the total referrals) were positive: 36 patients with MPS, 6 with mucolipidosis (1 type I, 1 type II and 4 type III) and 3 with mannosidosis. Sanfilippo B was not only the most frequent type III MPS but also the most frequent MPS identified in our study. Sphingolipidoses and other lysosomal disorders were diagnosed in 47 cases and non-lysosomal disorders in 19 cases. In our experience Gaucher disease, Sanfilippo B and Hunter syndrome are the most frequent lysosomal disorders in Greece accounting for 23.4%, 17.0% and 7.6% respectively of all diagnosed cases. 13% of the patients originated from Thessaly including 5/16 Sanfilippo B, 2/3 Morquio B, 2/3 Maroteaux-Lamy, 2/6 Metachromatic leukodystrophy and 2/12 Gaucher type 1.