Calf diarrhea continues to be the major problem of calves in the neonatal period. The effect of zeolites has been increasingly studied in ruminant health in recent years. In the present study, the efficacy of cristobalite, a zeolite, in neonatal calf diarrhea was studied first time. For this purpose, twenty-five neonatal calves with diarrheas were divided into two groups, and Group 1 (n=12) received conventional treatment and Group 2 (n=13) received cristobalite (Zoosorb 10 mg/kg) orally 3 times a day in addition to conventional treatment. Escherichia coli k99 and CS31a, bovine rotavirus and bovine coronavirus were isolated from fecal samples at the beginning of the treatment, on the third day and before discharge. It was determined that the recovery period in Group 2 was 0.95 (20.6%) days shorter than in Group 1 (p<0.05) while no viral agents were found on the fifth day in Group 2, viral shedding continued in 4 of 5 calves in Group 1. In conclusion, the study revealed that cristobalite speeds the recovery time and possibly decreases viral shedding in neonatal calf diarrhea, demonstrating a remarkable efficiency in the treatment.