Uterine diseases affect 25% of dairy cows in the United States and often develop from retention of the placenta. Expulsion of the placenta is a highly regulated inflammatory process. In healthy ruminants, a pro-inflammatory and chemoattractive response facilitates parturition and the expulsion of fetal membranes. Mechanisms by which dysregulation of uterine immune responses impair this process, particularly the role of caruncle macrophage phenotype in the expulsion process, are poorly understood. Our study compared uterine caruncle macrophage phenotypes in multiparous dairy cows on d 1 of lactation with either retained (RET, n = 5) or normal expulsion (NOR, n = 5) of placenta. Monocyte/macrophage cells were isolated from the stromal vascular cell digest of uterine caruncles by magnetic activated cell sorting using an anti-bovine-CD172a antibody. Further, transcriptional and protein expression studies were performed on uterine caruncles. A linear statistical model was used to detect differences between NOR and RET cows. Compared with NOR, RET samples had lower CD14⁺/CD16⁺ (pro-inflammatory phenotype) expression (P = 0.003) in caruncle monocyte/macrophage population. Compared with NOR, RET enhanced the expression of M2 associated genes CD206, CLEC7A, RNASE6 (P < 0.07) following transcriptional analyses. In addition, RET decreased STAT3 activation compared with NOR (P = 0.06), possibly indicating impaired proteolytic activity at the caruncle/cotyledon junction. Our studies demonstrate that macrophage populations in the caruncle of cows with RET placenta have a strong M2 macrophage polarization or an insufficient M1 macrophage stimuli. This may lead to reduced chemotactic capacity to recruit immune cells into the caruncle thus impairing the inflammatory, phagocytic, and proteolytic processes necessary for placental expulsion. Elucidating the role of macrophage phenotype during placental expulsion has the potential to develop preventative strategies for uterine disease in postpartum dairy cows.