Previous studies showed that strontium (Sr) as well as fluoride (F) can enhance enamel remineralization. The aim of this study was to evaluate the effects of Sr in combination with F on enamel remineralization in vitro. Sixty enamel specimens obtained from caries free human premolars were demineralised to produce caries-like lesions. Half of each lesion was covered with nail varnish as an untreated control. The specimens were then randomly divided into F and Sr+F treatment groups. The F group was exposed to remineralizing solutions (1.5mM CaCl(2), 0.9 mM KH(2)PO(4)) containing 1 ppm, 0.1 ppm or 0.05 ppm F. The Sr+F treatment group was exposed to the same solutions including 10 ppm Sr. After 2 weeks, lesion depth, mineral loss and percentage enamel remineralization were determined using transversal microradiography. There was a significant decrease in mineral loss in all groups (p<0.001). Lesion depth was significantly reduced for all groups (p<0.05) with the exception of group F. Remineralization was significantly affected by F concentration (p=0.000). The participation of Sr resulted in a significant enhancement of remineralization (p<0.001) with a synergistic effect of the Sr+F combination (p<0.01). It was concluded that while the remineralizing process was affected by the concentration of F, there was also an interaction between F and Sr when they were used in conjunction.