Objective: The objective of this study was intended for evaluation the effect of different surface treatments on microhardness and flexural strength of two types of resin ceramics. Materials and Methods: A total number of 140 samples were used in this study (70 samples for each test). This samples were divided into two equal groups according to materials (Vita Enamic [ENA] and Lava Ultimate [LVU]), then each group was subdivided according surface treatments into five subgroups Gr 1; no surface treatment (control), Gr 2; alumina particles with size (50µm) for sandblasting, Gr 3; alumina particles with size (110µm) for sandblasting, Gr 4; etching by plasma technology, Gr 5; etching by hydrofluoric acid (n=7). Microhardness was measured by using Digital Display Vickers Microhardness Tester andflexure strength by using Universal Testing Machine. Results: The results of this study revealed that; Control group of ENA recorded statistically significant highest microhardness. Control group of LVU recorded statistically significant highest flexure strength.  Conclusion: Surface treatment has adverse effect on microhardness and flexure strength of both resin ceramic materials.