The study was conducted to determine the effects of yeast culture ( YC) on growth performance，slaughter performance and meat quality of finishing cattle．

Seventy-five 17-month-old Simmentals Crossbred beef cattle with similar body weight were randomly assigned to 5 groups with 15 cattle per group．The control group ( C0 group) was fed a basal diet without YC supplementation，two experimental groups were fed the basal diet supplemented with 100 ( L100 group) and 150 g /d ( L150 group) YC in the last experimental period ( the 61th to 120th day) ,respectively; and the other two experimental groups were fed the basal diet supplemented with 100 ( W100 group) or 150 g /d ( W150 group) YC in the whole experimental period ( the 1stto 120th day) ，respectively．The pre-experimental period lasted for 14 days，and the experimental period lasted for 120 days．

The results showed as follows:

1 ) the average daily gain of cattle of W150 group was 1.02 kg /d，which was higher than C0，L150 and W100 groups by 10.8%，8.5% and 12.1%，respectively，and was higher than L100 group by 7.4%.The ratio of feed to gain of cattle of W150 group was significantly lower than that of C0 and W150 groups.

2) The back fat thickness of cattle of L150 group was significantly higher than that of other groups，the back fat thickness of cattle of W100 and W150 groups was significantly higher than that of C0 group; the marbling grade of cattle of W100 group was 2.81，which was significantly higher than that of C0 group.

3) The longissimus dorsi dripping loss of L150 group was significantly lower than that of C0 and W150 groups，the longissimus dorsi cooking loss of C0 group was significantly higher than that of L150 and W150 group.

4) The longissimus dorsi oleic acid percentage of W150 group was significantly higher than that of L100 group，and the linolenic acid percentage was significantly lower than that of W100 group.The longissimus dorsi twitocene-enoic acid percentage of C0 group was significantly higher than that of L100 group.There were no significant differences in all longissimus dorsi amino acid contents among all group.

In conclusion，dietary supplemented with 150 g /d YC in the whole experimental period( the 1st to 120th day) can increase the growth performance and improve the meat quality of cattle，and dietary supplemented with 150 g /d YC in last experimental period ( the 61th to 120th day) can improve the meat quality of cattle．