Aim: To evaluate the clinical and radiological response of primary molars to direct pulp capping with calcium sulfate hemihydrate. Materials and methods: Forty primary molar teeth in 40 healthy children aged 5-9 years were treated by direct pulp capping. Teeth were randomly assigned to two groups (n=20) according to material used for capping, as follows: Group 1: calcium hydroxide cement (Dycal); Group 2: calcium sulfate hemihydrate (Dentogen). All teeth were restored with a conventional glass ionomer base (Fuji IX) and amalgam. Results: After 12 months, the overall success rate of direct pulp capping was approximately 75% (24/32 teeth, excluding exfoliations). The success rate did not differ significantly between calcium hydroxide and calcium sulfate hemihydrate treatment. Conclusion: Calcium sulfate hemihydrate was found to be as successful as calcium hydroxide for direct pulp capping of primary molars with Class I cavities. Further histological studies are needed to support these findings.