The objective of this study was to determine how feed sorting behavior of dairy cows is altered in response negative energy balance. Holstein cows (n = 30; DIM = 59 ± 5) were followed for 2 wk where they were fed (on a DM basis) a lactating diet (NE_L = 1.66 Mcal/kg; 68% forage) and produced 44.6 ± 1.2 kg/d of milk. To induce negative energy balance, cows were then exposed for 3 wk to a TMR formulated for a 12% reduction in energy available for milk (NE_L = 1.56 Mcal/kg; 73% forage). Blood samples were taken 1x/wk during the baseline period and every 4 d while on the treatment diet and analyzed for NEFA and BHB. TMR samples (fresh and orts) were collected every 3 d and separated into: long (>19 mm), medium (<19 mm, >8 mm), short (<8 mm, >4 mm), and fine (<4 mm) particles. Feed sorting was calculated as actual intake of each particle fraction expressed as a % of predicted intake. Data were analyzed in repeated measures, mixed-effect linear regression models. During the baseline period cow NEFA and BHB averaged 0.29 ± 0.04 mmol/L and 0.71 ± 0.08 mmol/L, respectively. During the experimental period, NEFA and BHB increased (P < 0.001) to 0.32 mmol/L and 1.00 mmol/L, on average, with a peak of NEFA (0.59 ± 0.06 mmol/L) and BHB (1.12 ± 0.11 mmol/L) occurring 4 d after dietary change. During the baseline period, cows sorted against long particles (95.3 ± 1.4%), did not sort medium particles (99.8 ± 0.2%), and sorted for short (101.1 ± 0.8%) and fine (101.8 ± 0.6%) particles. During the experimental period, cows increased (P = 0.008) sorting against long particles (92.2 ± 1.3%), continued to not sort medium particles (100.0 ± 0.1%), increased (P = 0.002) their sorting for short particles (102.1 ± 0.8%), and continued to sort for fine (102.5 ± 0.6%) particles. In the baseline period there was no association (P > 0.6) of feed sorting and blood NEFA levels. In the experimental period, higher NEFA levels were associated with greater sorting against long particles (% long sorting = −15.0 × NEFA(mmol/L) + 97.0; R² = 0.20; P = 0.01). Further, in that period higher NEFA levels were associated with greater sorting for short particles (% short sorting = 4.8 × NEFA(mmol/L) + 100.5; R² = 0.18; P = 0.02). The results indicate cows alter their feed sorting behavior in response to experience of a period of negative energy balance.