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Fifteen multiparous rumen-cannulated Holstein cows were assigned to one of five treatments in a replicated 5 × 5 Latin square design. The treatments were low-starch (<b>LS</b>) (22.8 ± 1% of dry matter; <b>DM</b>) without autolyzed yeast (<b>AY</b>; <b>LS0</b>, control), high-starch (HS) (31.2 ± 4% of DM) without AY (<b>HS0</b>), and HS with either 15 g (<b>HS15</b>), 30 g (<b>HS30</b>), or 45 g (<b>HS45</b>) of AY supplementation. Cows in HS0 had increased (<i>p</i> < 0.03) dry matter intake (<b>DMI</b>; 24.9 kg/d) and energy-corrected milk (<b>ECM</b>; 34.4 kg/d) compared to cows in LS0 (19.9 and 31.3 kg/d, respectively). There was a tendency for a quadratic treatment effect for feed efficiency (ECM/DMI, <i>p</i> = 0.07) and crude protein (<b>CP</b>) apparent digestibility (<b>AD</b>) (<i>p</i> = 0.09). Cows in HS45 tended (<i>p</i> = 0.09) to have increased DMI (25.6 kg/d) compared to cows in HS0 (24.9 kg/d). Cows in HS0 had greater (<i>p</i> < 0.04) milk protein nitrogen (<b>N</b>; 166 g/d) and microbial N production (161 g/d) than those in LS0 (140 and 138 g/d, respectively). In conclusion, the addition of AY tended to improve DMI, feed efficiency, and CP AD when cows were fed the HS diet.