The construction industry uses cement as a raw material. However, the production of cement requires a significant amount of energy and results in increasing CO2 emissions, leading to environmental pollution, and various health impacts on individuals. Moreover rice husk and waste paper are agricultural and industrial waste respectively that result from environmental pollution and disposal problems. Considering the environment, it is important to handle waste materials. The objective of this study was to investigate how the fresh, mechanical, durability, and microstructure properties of mortar are affected when rice husk ash (RHA) and waste paper ash (WPA) are used as partial cement replacement along with material characterizations. The combination of rice husk ash (RHA) and waste paper ash (WPA) in a (2:1) ratio was incorporated into the cement at different percentages (0,5, 10, 15, 20, and 25%), and a total of 288 mortar cube test samples were prepared for the study. The experimental results revealed that the replacement of RHWPA increasing the slump flow of mortar was decreased as compared to control specimens. However 15% of RHWPA mixes, the mortar’s Compressive strength, and UPV have been improved, particularly in the later age of mortars. Moreover, the incorporation of RHA and WPA enhances the mortar’s durability. The microstructure study reveals that 15% replacement of RHWPA mixes was extremely dense as compared to the control specimen. It was concluded and recommended that RHWPA can enhance mechanical (compressive strength, and UPV), durability (water absorption, porosity, and sulfate resistance), and microstructural (SEM, DTA, TGA) properties of mortar up to 15% of RHWPA replacement, and can be used as a partial replacement for cement. Keywords: Cement Mortar, Durability, Mechanical Performance, Microstructure, Rice Husk Ash, Waste paper Ash.