In view of the current low level of R&D and production of synbiotics functional dairy products in China， most of them use the mixed fermentation of probiotics and traditional yoghurt bacteria. In this paper， with 18 newly probiotics isolated from natural fermented food， health products and microbial preparations and these strains contained in three commercial yoghurt starters used as test strains， the traditional yoghurt fermentation strains of Lactobacillus bulgaricus and Streptococcus thermophilus as control strains， by researching the curd time， acid producing ability and sensory quality of the fermented milk by these strains and analyzing the proliferative effect of these strains using stachyose， the probiotic which can utilize stachyose as a prebiotic to ferment the synbiotic yoghurt products was screened； the growth curve of the screened strain in pure cow’s milk basic medium was determined； the optimum addition amount of stachyose in the prebiotic proliferation medium was studied； the fermentation process conditions of yoghurt products with stachyose-probiotics sybiotics were optimized； the quality of 0 d and stored 21 d synbiotic yogurt product was tested. The results showed that the newly probiotic Lactobacillus casei 07-211 had the potential to ferment milk and can significantly proliferate with stachyose， and the number of viable cells increased from 3.19×108 CFU/mL to 2.05×109 CFU/mL. The optimum addition amount of stachyose in the prebiotic proliferation medium was 0.8%； the best process conditions for Lactobacillus casei 07-211 pure fermented stachyose synbiotic yoghurt were 3% inoculation， 4% sucrose addition and fermentation temperature at 42 ℃. The fermented synbiotic yoghurt products with the optimal conditions， whose curd time was at 4.15 h， pH was 4.65， titration acidity was 64.27 °T， the viable cell numbers was 3.96×109 CFU/mL， the sensory evaluation score was 8.78（10-point scale）， the quality of 0 d and stored 21 d synbiotic yoghurt exceeded the national standard. This study provided theoretical basis and technical support for the industrial production of Lactobacillus casei pure-fermented stachyose synbiotic yoghurt products， and also provided ideas and methods for the development and application of other functional synbiotics.