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As wildfires have increased in frequency and size throughout the Great Basin, post-fire rehabilitation activities have become important in reestablishing resilient sagebrush steppe communities. Many rehabilitation treatments fail when perennial grass seedlings do not establish. This can be due to pre-fire site condition, burn severity, and presence of non-native species, which leads to varying post-fire biotic and abiotic conditions. Domestic livestock grazing presents a further challenge to seedling establishment after fire with pressure to reintroduce grazing as early as possible. There is little research addressing the question of when is ecologically appropriate to re-implement livestock grazing after wildfire in sagebrush ecosystems, and none addressing grazing impacts to seedlings planted in rehabilitation treatments. We examined the effect of varying seedling and adult plant density and timing of post-fire grazing on relative growth rates, survival, and canopy cover of perennial grass seedlings in Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) communities. We analyzed within season plant growth rates using a non-linear mixed model approach, and end of season plant density and cover using a linear mixed model approach. Spring grazing resulted in faster within season growth rates as compared to no grazing and fall grazing. Adult and seedling removal treatments resulted in lower plant density, while only seedling removal resulted in lower plant cover as compared to no plant removal. Timing of grazing had no effect on plant density or percent cover.