Aim of the study: to assess the microleakage of the new zinc reinforced glass ionomer cement restoration (Chemfil Rock) in comparison to two resin modified glass ionomer cement restorations (Fuji IX) and (Riva self cure) in primary teeth and assess the microshear bond strength of these three glass ionomer cement restorations. Materials and Methods: The study included a total number of 60 carious freshly extracted upper and lower primary molars. Selected teeth will be divided into three main groups according to restorative material used : Group 1: 20 teeth restored with Chemfil Rock glass ionomer, Group 2 : 20 teeth restored with Fuji IX glass ionomer,Group 3: 20 teeth restored with Riva Self Cure HV glass ionomer. Then, each group will be subdivided into another two groups according to the test used: Group A: 10 teeth used to test the microleakage, Group B: 10 teeth used to test the microshear bond strength.Results: The results showed that Fuji IX glass ionomer recorded the highest leakage score mean value followed by chemfill then Riva Self cure HV. It recorded the lowest leakage sore mean value. It also showed that Riva Self cure HV group recorded statistically significant highest microshear bond strength mean value followed by Chemfill group while lowest microshear bond strength mean value was recorded by Fuji IX group.Conclusion: It was concluded that Fuji IX glass ionomer group recorded the highest microleakage score while the lowest microleakage score was recorded by Riva Self Cure HV glass ionomer. Riva Self Cure HV recorded the highest microshear bond strength ; while the lowest microshear bond strength was recorded by Fuji IX group