Niemann-Pick disease (NPD) refers to a group of lysosomal storage diseases with autosomal recessive inheritance pattern that cause abnormal metabolism of lipids. NPD clinically is placed into four different types, A, B, C and D. Types A and B occur due to defects in SMPD1 gene involved in metabolism of sphingomyelin. Types C and D are caused by mutations in NPC1 and NPC2 genes involved in metabolism of cholesterol. Diagnosis of the disease is based on clinical assessment and then biochemical and finally molecular genetic testing. Molecular genetic testing, include sequencing, use of multigenic panel as well as indirect methods using polymorphic markers located in the proximity of the genes associated with the disease. In this article the information regarding the Niemann-Pick disease and its diagnosis with emphasis on types A and B was reviewed.