Abstract: This paper reported an investigation on the effects of three different cross-linking methods, i.e. CaCl2-crosslinking, HCl-crosslinking and mixed CaCl2+HCl-crosslinking, on the mechanical and physical properties of seaweed residue mulch film. The results indicated that the seaweed residue mulch film achieved the tensile strength of 15.87 MPa and maximum elongation at break of 8.220 % at the crosslinking time of 15 min when a mixture of CaCl2 and HCl was used at the concentrations of 1.5 and 0.5 wt%, respectively. Meanwhile, the seaweed residue mulch film obtained a water vapor permeability of 1.454×10-9 g·m/m2·h·Pa and maximum transmittance of 7.556 %. The seaweed residue mulch film was found to gain the optimal comprehensive properties in this condition.