Abstract: Due to the rapidity with which structures are being constructed nowadays, particularly in developing nations like Nigeria, concrete blocks have become the most commonly used building material. Even though they arent very light, concrete blocks have a high compressive strength, and the ingredients for concrete are easy to find. Some industrialized nations are shifting away from utilizing concrete blocks due to their lack of sustainability, which leads to their being environmentally unfriendly, in favor of compressed earthen blocks (CEB), which are more sustainable in terms of getting resources and more ecologically friendly. This paper investigated the thermal and mechanical performance of compressed earth blocks. The percentage of cement was investigated with 0%, 2%, 4%, and 6% cement sample. Results obtained revealed that the compressive strength was notably high at 28 days after curing, with strength of 10.30 N/mm2. After 28 days of curing, a high UPV of 8622m/s and 8660m/s for 4 and 6 percent cement replacement was reported respectively.