The aim of this study was to compare the effect of different immersion protocols into various acidic media on the surface roughness of various glass ionomer-based dental restorative materials in vitro. The total number of 200 specimens were prepared from 5 different restorative material groups. Ten specimens from each group were then immersed into one of the tested beverages including; Coca-Cola, Iced-Tea, orange juice and distilled water (control). All specimens were kept in oven at 37 degrees C for designated time periods of 1 day, 1 week, 1 month, 3 months, 6 months and 1 year and solutions were renewed weekly. Surface roughness measurements were performed at baseline and after each immersion period. The surface roughness of all glass ionomer-based restorative materials were affected by immersion with acidic media to a degree. For Glass Carbomer, there were steady increases in surface roughness in Ice Tea and orange juice (p < 0.05). The only significant increase in surface roughness of Fuji IX was found in orange juice (p < 0.05). However, the difference was not significant in coke and ice tea in comparison to distilled water (p > 0.05). When compared with distilled water, surface roughness of Chemfil Rock had increased significantly in coke and orange juice (p < 0.05). Surface roughness values of F2000 had increased significantly in coke and ice tea compared with distilled water (p < 0.05). For Dyract XP, only significant increase was found in coke compared with distilled water (p < 0.05). In conclusion, compomers were determined as the most robust materials comparing the surface roughness of the other glass ionomer based materials particularly used in pediatric dentistry. The surface degradation following immersion with acidic media is a multifactorial process, not only the pH and composition of the acidic environment, but also the type and composition of the exposed restorative material have influence on this process.