This work is a comparative study between sand mortars of different geological origins, intending to highlight their influence on mortar properties. For this purpose, five sand types and the cement CEM II/B-P 42.5R were used for the formulation of mortars with identical W/C ratios. These are the "Sanaga" sand from the Sanaga River, the "Wouri" sand from the Wouri River, the Nyambaka basalt sand, the Meiganga granite sand, and the Leboudi gneiss sand. These sands were characterized and classified according to their physical, chemical, and mineralogical properties. They were then used to make mortars. From the results of the setting time tests carried out on the mortars, it appears that the initial setting time varies from 195 min for MS04 to 210 min for MGN03, while passing by MW05 (200 min), MB01 (198 min), and MGR02 (196 min). The final setting time varied from 496 min (MGR01) to 510 min (MGN03) with an average of 300 min over and above the initial setting time to reach the final setting time. The flexural strength tests of the mortars show that the crushed sands have better properties than the alluvial sands. They vary from 1.64 to 2.18 MPa at 2 days, from 3 to 3.90 MPa at 7 days, and from 7 to 14.84 MPa at 28 days. As for the compressive stress tests, the results show that the quarry sand mortars studied have higher average compressive strengths than the alluvial sand mortars, with basalt sand offering the best performance. These strengths range from 6.35 to 10.83 MPa at 2 days, 7.55 to 18.96 MPa at 7 days, and 22.81 to 34.58 MPa at 28 days, with 34.58 MPa for the basalt mortar. The mineralogical analysis of the mortars reveals the presence of cement hydrates and non-hydrated phases in all the mortars. They also show the absence of minerals brought by the sands that could chemically interfere in the setting process.