Sago starch is an organic filler that provide biodegradable properties to natural and synthetic rubber latex thin film products upon disposal. There is antagonism effect between biodegradability and mechanical properties of sago filled XNBR latex films where it prone to agglomerate and incompatible with latex system which, eventually reduced the mechanical properties of the latex films. The objective of this research is to develop a small particle size sago starch to improve the mechanical properties and biodegradability of latex films upon disposal. The native sago starch (NSS) was hydrolyzed with different hydrolysis condition at different temperature, acidity and duration. The results showed that the optimum synthesis parameters of preparation acid hydrolysis sago starch was at 2.18 M sulphuric acid under non heated condition (27°C) for 7 days. The particle size of native sago starch is 1.233 µm and it reduced to 0.313 µm under same condition. It was found that the AHSS has improved mechanical properties and swelling resistance of latex films as compared to NSS filled NR latex films and NSS filled XNBR latex films. The biodegradation assessment by mass loss analysis indicates AHSS filled NR latex and XNBR filled latex films has higher degree of biodegradation rate. Overall addition of AHSS has increased the mechanical and biodegradable properties of both type of latex films (NR and XNBR) compared to NSS.