This study evaluated alkaliAlkali-activated pastes based on metakaolinMetakaolin (MK) with partial replacement by blast furnace slag (BFS), analyzing their compressive strength after 8 and 24 h at 38 and 60 °C, in addition to rheology and mini-slump tests, in order to evaluate their rheological properties and mechanical performance of these pastes for applications in oil wellsOil well. The results indicate that the increase in curing temperature favored the mechanical resistance of the pastes, especially those with a higher BFS content. The sample with 20% BFS (G2) presented the best results, exceeding the normative criteria for specifications. In terms of rheology, the alkaliAlkali-activated pastes include superior components to Portland cement, but, according to the literature, they remain pumpable, confirming their prediction for well cementing. However, this preliminary analysis is limited to rheological and mechanical tests, and further tests are necessary to validate their applicability.