Objectives: This in vitro study was designed to evaluate caries excavation time, chemical and morphological changes of the excavated dentine surface following caries excavation with sodium hypochlorite based chemo-mechanical caries removal Systems. Materials and Methods:A total number of 40 human molars exhibited moderate caries (ICDAS 5) were used in the current study, The selected molars were randomly divided into 4 groups according to the caries excavation method (n=10). Group (1), caries excavation was performed by Carisolv ™ gel. Group (2), caries excavation was performed by the New Carisolv. Group (3), caries excavation was performed by low-speed round carbide bur. Group (4), caries excavation was performed with komet (ceramic and polymer) burs incorporated with the New Carisolv system (without using the CMCR gel) this group is considered as the positive control group of the study. Results: A statically significance difference were found regarding caries excavation time per minute (mean ± SD) among the four groups; group 3 showed the lowest mean in time followed by group 4,  Then group 2 and lastly group (1) showed the highest time (2.04±0.40, 4.20±0.49, 5.35±0.69 and 7.34±1.13 respectively). No significance difference were found among the four groups regarding to calcium / phosphorus (Ca/P) ratio wt%. Conclusions: The outcomes of the present study showed that sodium hypochlorite based chemo-mechanical caries removal agents provided longer excavation time and potentially enhanced morphological features of residual dentine in comparison with other caries excavation methods. Keywords: Carisolv; Chemo mechanical caries removal