Abstract: This study investigates the flexural strength performance of sorghum husk ash (SHA) blended cement, laterized concrete cured in water. The research evaluated the physical and chemical properties of SHA and laterite and examined their combined influence on concrete flexural behaviour. SHA replaced Ordinary Portland Cement at 0%, 10%, and 20%, while laterite replaced fine aggregate at 0%, 10%, and 20%, producing a 3 × 3 factorial experimental design. A total of 81 beam specimens (100 mm × 100 mm × 500 mm) were cast and cured for 7, 14, and 28 days before flexural testing under third-point loading. Results showed consistent strength development with curing age for all mixes. However, increasing SHA and laterite contents resulted in gradual reductions in flexural strength. The control mix (0% SHA, 0% laterite) achieved the highest 28-day strength of 17.17 N/mm². Two-way ANOVA indicated that both SHA and laterite replacement levels significantly influenced 28-day flexural strength (p < 0.05), while their interaction effect was not statistically significant. Findings suggest that up to 10% SHA replacement can be adopted without significant loss in flexural performance, supporting the sustainable utilisation of agricultural waste in laterized concrete production.