Abstract: With the low-field NMR and texture analyzer, the factors influencing the strength and relaxation properties of agar gel were discussed, and the gel mechanism was analyzed.The results suggested that: with the increase of agar mass fraction, agar gel strength was increased.When the p H was 6.0 ~ 7.0, gel showed the best strength. Potassium chloride, xylitol, sucrose could improve agar gel strength to some extent. Especially, the mass fraction of 0.2% ~ 0.3%, 9% and 6% showed the maximum strength of agar gel.Appropriate proportion of konjac gum, locust bean gum and carrageenan could generate synergies with agar, and generated the strongest synergies in their respective proportion of 15%, 5% and 10%.Calcium chloride, sodium chloride, and β-cyclodextrin hindered the formation of the gel, and reduced agar gel strength. The results indicated that the agar gel relaxation time T₂₃ and gel strength significantly ( p < 0.01) negatively correlated. In other word, the smaller the water mobility was in the gel, the greater the gel strength was.