Aim: The aim of this study was to evaluate the efficacy of intracoronal bleaching using non thermal atmospheric pressure plasma and its effect on pulp chamber dentin structure. Materials and methods: Two types of commercially available hydrogen peroxide bleaching systems were used in this study with a concentration of 32% (White smile GmbH). Thirty eight single rooted premolars were collected. The teeth were sectioned in half longitudinally in a mesio-distal direction and specimens were prepared according to the testing method used. Specimens were stained with a prepared standardized coffee solution. The sectioned teeth were divided into four groups according to the type of bleaching protocol used. Color measurements were done by a spectrophotometer before bleaching, one day and one week after bleaching for all the experimental groups. Universal Testing Machine with cross head speed of 1 mm/min was used for measuring microshear bond strength of the four investigated groups before and after bleaching. Data were analyzed statistically by: Duncan Multiple range test for means comparison and Paired t test for evaluating the effect of time and intervals on different parameters within each bleaching protocol. The significance level was set at P ≤ 0.05. Results: The results showed different findings among the bleached groups when evaluated after 1 day and 7 days. It was found that non thermal atmospheric plasma has a stronger bleaching effect than LED light when used as an activating method. Furthermore, the light bleached group showed a significant decrease in the microshear bond strength values after bleaching. While, there was no statistically significant difference in microshear bond strength values of the other three groups. Conclusion: The application of non thermal atmospheric pressure plasma is a promising method for intracoronal bleaching.