This study presents a comprehensive comparison of hemp, kenaf, and sisal fibres as internal curing materials in concrete production. Internal curing has emerged as an effective technique to mitigate autogenous shrinkage and enhance concrete durability. Natural fibres offer sustainable alternatives to conventional internal curing agents. The research evaluates the water retention capacity, moisture release characteristics, and effects on concrete properties of these three fibre types. Experimental results demonstrate variations in absorption rates, desorption kinetics, and its impacts on mechanical properties of concrete among the fibres. The results indicate that hemp fibres exhibit superior water retention, while kenaf shows optimal moisture release patterns. Sisal fibres contribute significantly to improved strength. The study also assessed the effect of fibre dosage on the workability, compressive strength, and cost-effectiveness of each fibre type. This comparative analysis provides valuable insights into the selection of natural fibres for internal curing, considering both performance and sustainability aspects in concrete technology.