The development of hepatic steatosis involves the enhanced hepatic uptake of fatty acids which induces sphingomyelin (SM) synthase activity. Increased hepatic SM levels may limit the availability of choline for the synthesis of phosphatidylcholine (PC), a glycerophospholipid required for liver triacylglycerol (TAG) secretion. Alternatively, the presence of inflammation provokes acid sphingomyelinase (i.e., sphingomyelin degradation) which is secondary to PC degradation and the subsequent synthesis of diacylglycerol (DAG). Our objective was to determine how bovine liver phospholipids and acylglycerols change during the progression of hepatic steatosis. Thirty multiparous Holstein cows were enrolled −28 d prepartum and fed diets formulated to meet or exceed requirements. Liver tissue was biopsied at d −28, 5, and 14, relative to parturition. Untargeted lipidomics was performed using quadrupole time-of-flight mass spectrometry. Multivariate analysis of normalized, auto-scaled lipidomic data included ANOVA and Pearson correlation coefficient procedures. Total hepatic lipid content increased by d 14 postpartum, relative to d −28 (9 versus 4% lipid; P < 0.05). Mass spectrometry monitored 30 SM, 35 PC, 76 TAG, and 24 DAG. Uniform increases in 19 DAG and 74 TAG were observed during the transition from gestation to lactation (P < 0.05). Moreover, total DAG was strongly correlated with liver lipid content and total TAG (r = 0.74 and 0.97, respectively; FDR <0.05). Nonuniform changes in hepatic SM and PC were observed. A total of 17 SM (e.g., SM 42:0 and 44:2) and 13 PC (e.g., PC 34:2 and 36:1) increased with time (P < 0.05), whereas 10 SM (e.g., SM 48:3 and 34:2) and 16 PC (e.g., PC 40:4 and 42:6) decreased with time (P < 0.05). Liver lipid content was positively correlated with 17 SM and 10 PC (FDR <0.05) and negatively correlated with 10 SM and 18 PC (FDR <0.05). The majority of DAG were inversely related to polyunsaturated PC (e.g., DAG 32:2 versus PC 42:5; r = −0.84, FDR <0.05). We conclude that bovine steatosis develops with a uniform accrual in hepatic DAG and TAG, as well as nonuniform changes in liver SM and PC.