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Grazing by domestic livestock is the most common and economical use of grasslands. Plants adopt different reproduction tactics in response to herbivory disturbances under different grazing intensities. Grazing effects on reproduction of the dominant species (Stipa breviflora) in a desert steppe are still poorly understood. To evaluate effects of stocking rates on S. breviflora reproduction, a sheep grazing experiment was carried out in 2015 using a randomized complete block design, which was grazed from 2003 to 2017 under four stocking rates [0 (control, CK), 0.15 (light grazing, LG), 0.30 (moderate grazing, MG), and 0.45 (heavy grazing, HG) sheep unit hm-2 month-1] in the desert steppe of Inner Mongolia, China. Seed yield of S. breviflora was highest in LG (0.76 � 0.09 g tussock-1) (Mean � SE) while lowest in HG (0.20 � 0.02 g tussock-1) (P < 0.0001). A more pertinent explanation is the ratio of seed biomass (28.85 � 1.80% vs. 20.72 �1.15%), reproductive branches (28.55 � 1.87% vs. 11.93 � 0.94 count tussock-1) and the ratio of reproductive branches (89.98 � 2.07% vs. 71.78 � 2.24%) were highest in LG and lowest in HG (P < 0.0001). Tillering was the primary asexual reproduction for S. breviflora, both tillers (57.97 � 2.93 count tussock-1) and clump diameter (5.19 � 0.53 cm tussock-1) of S. breviflora were increased by LG (P < 0.05). While the depth of tiller below the soil surface decreased as stocking rates increased (P = 0.03), this made tillers easier to come out from compacted soil trampled by sheep. Both sexual and asexual reproduction of S. breviflora were stimulated by LG while inhibited by increase stocking rates. Both MG and HG were detrimental to S. breviflora renovation and increased the risk of grassland degradation.