Dyscalculia () is a disability resulting in difficulty learning or comprehending arithmetic, such as difficulty in understanding numbers, learning how to manipulate numbers, performing mathematical calculations, and learning facts in mathematics. It is sometimes colloquially referred to as "math dyslexia", though this analogy is misleading as they are distinct syndromes.

Dyscalculia is associated with dysfunction in the region around the intraparietal sulcus and potentially also the frontal lobe. Dyscalculia does not reflect a general deficit in cognitive abilities or difficulties with time, measurement, and spatial reasoning. Estimates of the prevalence of dyscalculia range between 3 and 6% of the population. In 2015 it was established that 11% of children with dyscalculia also have ADHD. Dyscalculia has also been associated with Turner syndrome and people who have spina bifida.

Mathematical disabilities can occur as the result of some types of brain injury, in which case the term acalculia is used instead of dyscalculia, which is of innate, genetic or developmental origin.