The objective of this study is to investigate the effects of l-arginine (Arg) on the physicochemical and gel properties of chicken actomyosin. The results showed that Arg increased the content of surface hydrophobicity and reactive sulfhydryl group of chicken actomyosin, but decreased storage modulus (G0). Also, Arg enhanced the first thermal transition temperature (TM1) but decreased the second thermal transition temperature (TM2). The addition of Arg favored to form a dense and uniform gel with the increased water holding capacity (WHC), strength and transverse relaxation time (T2). These results suggested that Arg may result in the formation of a uniform and continuous gel by changing the structural and thermal behavior of actomyosin in turn, ultimately contributing to the elevated WHC and strength. The results may provide new insight into the effects of Arg on the WHC and texture of meat products in the previous literatures.