This study was conducted to evaluate the effect of probiotic - vizyme (VIZ) on reproduction performance of Luong Phuong (LP) layers. A total of 144 LP pullets of 16 weeks old were divided into 12 groups, each with 12 pullets. These were randomly assigned to 4 treatments containing 0,05, 1.0 and 1.5 g of VIZ/liter of drinking water in completely randomized design with 3 replications for a study period of 22 weeks. Feed consumption, feed conversion ratio, egg production, egg quality, fertility, and hatchability were used as evaluation parameters. The results obtained showed that there was no significant difference among all the treatment groups in feed consumption, sexual maturity, survival rate and feed conversion efficiency (P0.05), whereas the mean body weight gain of the groups of 24 weeks placed on the treatment containing 1.0 to 1.5 g of VIZ/liter were significantly (P0.05) higher than the control groups. The results obtained also showed that there was no significant (P0.05) difference between all the treatment groups of layers in feed consumption, fertility and hatchability (P0.05) to an age of 37 weeks. On the other side, the mean weekly egg production and feed conversion efficiency during the laying period were significantly higher (P0.05) for the groups of layers placed on the treatment containing 0.5 to 1.5 g of VIZ/liter compared to that of the groups placed on the control treatments. In summary, the results of this study showed that inclusion of 0.5 to 1.5 g of VIZ/liter resulted in significant improvement in survival and growth rate, egg production, feed conversion ratio and egg quality parameters.