Tyramine is widely used in biochemical reagent, organic chemical and pharmaceutical intermediates. A strain capable of catalyzing L-Tyrosine to produce tyramine was isolated and identified as Providencia Ewing. After single-factor and orthogonal tests, the optimal culture conditions were determined as follows: beef extract 5 g/L, yeast extract 5 g/L, glucose 5 g/L, glycerine 5 g/L, K2HPO4 2 g/L, MnSO4 0.01 g/L, VB6 0.003 g/L, temperature 37 °C and pH 5.5. After optimization of the transformation conditions, 10 g/L of tyrosine was completely decarboxylation into tyramine in 3 h. The substrate was then supplemented every 3 h at a concentration of 10 g/L for 4 times, and it was found that the substrate could still be completely transformed into tyramine.