The purpose of this study was to determine flour uptake difference in enamel of primary teeth between Glass Ionomer Cement and Compomer filling. The sample was 30 maxillary first incisors divided into 2 groups. Each group consisted of 15 teeth. The first group was filled with Glass Ionomer Cement (Fuji IX ART, GC) and second group was filled with Compomer (Dyract, Dentsply). The measurement was in percentage, using Energy Dispersive X-Ray Spectrophotometry. T test exhibited significant difference of fluor uptake in enamel of primary teeth between Glass Ionomer and Compomer filling (t=1.1, p=0.0001) Fluor uptake of Glass Ionomer Cement filling in enamel of primary teeth was much more compare to Compomer filling