The objective of this study was to evaluate production performance in high-producing cows consuming diets containing hulled or hull-less barley as the grain source combined with low or high forage concentrations. The experiment was designed as a replicated 4 × 4 Latin square with 21-d periods and a 2 × 2 factorial arrangement of treatments (45 vs. 65% forage and hulled vs. hull-less barley). The cultivars utilized were Thoroughbred and Amaze 10 for the hulled and hull-less grains, respectively. Eight primiparous (610 ± 40 kg BW and 72 ± 14 DIM) and 16 multiparous (650 ± 58 kg BW and 58 ± 16 DIM) Holstein cows were fed once daily (1100 h) by means of a Calan gate system. Treatments consisted of: 1) 45% forage and hulled barley, 2) 65% forage and hulled barley, 3) 45% forage and hull-less barley, 4) 65% forage and hull-less barley. All variables were analyzed using the MIXED procedure of SAS. The statistical model included the effects of square, treatment, square by treatment interaction, period, cow within square, and the random residual error. Milk yield (41.8 kg/d; P < 0.76), milk lactose percentage (4.84%; P < 0.19), milk lactose yield (2.05 kg/d; P < 0.29), and body weight gain (0.64 kg/d; P < 0.79) did not differ among treatments. Dry matter intake tended to be lower for high-forage diets (25.4 vs. 26.8 kg/d; P < 0.07) and was not affected by grain type (P < 0.47). Milk fat percentage (3.91 vs. 3.50%; P < 0.01) and yield (1.60 vs. 1.49 kg/d; P < 0.03) were greater for high-forage than for low-forage diets but were not affected by grain type (P > 0.17). Milk protein percentage (3.13 vs. 3.07%; P < 0.01) and yield (1.33 vs. 1.26 kg/d; P < 0.03) were greater for high-forage than for low-forage diets but were not affected by grain type (P > 0.48). Milk urea nitrogen was reduced when feeding low-forage diets (15.4 vs. 14.1 mg/dL; P < 0.01) and hull-less barley (15.6 vs. 13.9 mg/dL; P < 0.01). Their interaction was not significant. In conclusion, feeding either hulled or hull-less barley as the energy source in high- or low-forage diets resulted in similar production performance in high-producing cows.