Background: Reading habits are believed to have an important role in the association between number and space; however, the effect of the spatial numerical association of response codes (SNARC) as a casual involvement has not been fully documented. Objectives: This study aimed to determine the SNARC effect in individuals with mixed-reading Persian language in which the text is read from right to left but the numbers are read from left to right. Moreover, because of the critical role of visuospatial attention in SNARC effect, which is impaired in patients with schizophrenia, the SNARC effect was also examined in a group of patients with schizophrenia. Methods: Using number comparison tasks and parity judgment tasks, the SNARC effect was first examined in a group of Persian speaking university students and then in a group of Persian speaking schizophrenic patients. Results: The results showed the standard SNARC effect in students with the mixed-reading habit. Moreover, the results revealed a comparable SNARC effect in schizophrenia patients and controls. Conclusions: Our results suggested that the direction of reading of numbers might influence the relationship between numbers and space, not the direction of text reading. Also, the semantic representation of numbers is preserved in patients with schizophrenia.