Our objective was to investigate which feed and housing management variables were associated with milk yield (MY) and rumination time (RT) in a compost bedded pack barn (CBPG). We used a data set from 2 pens of primiparous (PP) or multiparous (MP) Holstein cows from a commercial dairy farm in Argentina (Chiavassa Dairy Farm; −32° 02′ 60″ S, 61° 47′ 59″ W). Variables evaluated included: DM intake (DMI), TMR DM content, feed bunk orts percentage (FBO), TMR particle size distribution (PSD), and cow stocking density (CSD, m²/cow). All variables were recorded daily from May 2015 to December 2016. Milk yield (ALPRO, DeLaval) and RT (Heatime HR System, SCR) were averaged daily by pen and DMI was estimated by difference between feed offered and refused. The TMR PSD was measured using the 4-sieves PennState Particle Separator. The TMR DM content was determined with a forced-air oven for 2 h at 135°C. Cows were milked 3×/d and fed 2×/d with a TMR composed by corn silage, alfalfa silage, alfalfa hay, corn grain, soybean meal, and mineral premix that averaged 49.8 ± 1.1% DM, 15.8 ± 0.9% CP, 29.9 ± 5.3% NDF, and 2.89 ± 0.15 Mcal ME/kg DM (mean ± SD). We run Pearson correlations (r; R Core Team, www.r-project.org) to evaluate association between MY and RT, and the 5 variables. Milk yield was positively correlated (P < 0.01) with DMI (r = 0.50 for PP, r = 0.49 for MP), TMR DM content (r = 0.27 for PP, r = 0.28 for MP), RT (r = 0.24 for PP, r = 0.38 for MP), and CSD (r = 0.08 for PP, r = 0.37 for MP). Rumination time was positively correlated (P < 0.01) with 19 to 8 mm-sieve percentage (r = 0.45 for PP, r = 0.48 for MP), but it was negatively correlated (P < 0.01) with 8 to 1.18 mm-sieve percentage (r = −0.32 for PP, r = −0.28 for MP). Our results show that milk yield of Holstein cows housed in CBPB was positively associated with key feeding management variables such as DMI and TMR DM content but also with housing management variables such as CSD. On the other hand, RT was affected more by TMR PSD due to feed mixing management.