Introduction Gastroenterological disturbances and complains are often observed in autistic children. Micro and macroscopic laesions in gut mucosa called “colitis autistica” are observed during endoscopy. Faecal calprotectin is a marker of inflammation and it is useful tool in distinguishing between organic abdominal disorders and functional disturbances of digestive system.

Aim The aim of the study was the assessment of faecal calprotectin concentration in children with autistic spectrum disorders (ASD) and with abdominal complains.

Material and Methods In 26 children: mean age: 7,5 yr (3–17 yr) : 9 (35%) girls and 17 (65%) boys with autistic spectrum disorders faecal calprotectin concentration was measured in stool samples by ELISA using PhiCal Test by Calpro.

Results 24 children had normal level of FC (1,9–44,99 mg/kg), 2 of children had insignificantly elevated FC levels (59,72 and 189,6 mg/kg). Normal value 0–50 mg/kg.

Conclusions 1. Normal concentration of faecal calprotectin concentration indicate there is no inflammation state in mucosa of the intestine in children with autistic spectrum disorders. 2. To find out the reason of complains from digestive system we need further examinations like motility examinations and/or hormonal tests.