Postoperative complications persist as a significant cause of graft failure in liver transplantation. Identifying circulatory markers that predict such complications holds excellent clinical value. This study aimed to investigate serological indicators that can indicate early complications in adult liver transplantation. This study included 436 patients who underwent liver transplantation at our hospital, along with corresponding monitoring protocols. The differences and interactions of circulating indicators at various time points were analyzed using repeated measures analysis of variance. Post-hoc multiple comparisons were adjusted using the Bonferroni method. Restricted cubic spline regression models assessed non-linear associations between circulating markers, complications, and mortality. This study demonstrated significant time effects for all related markers, with substantial differences in complications and mortality for direct bilirubin and albumin. The restricted cubic spline model revealed a significant positive association between direct bilirubin and complications across three postoperative phases (p postoperative phase 1 = 0.0011, p postoperative phase 2 = 0.0001, p postoperative phase 3 = 0.0020). Conversely, albumin showed a significant negative association with complications in phases 1 and 2 (p postoperative phase 1 = 0.0001, p postoperative phase 2 = 0.0009). Furthermore, direct bilirubin was significant associated with increased mortality of postoperative phase 2 and phase 3 (p postoperative phase 2 < 0.0001, p postoperative phase 3 < 0.0001), while albumin showed a significant negative association with mortality (p postoperative phase 1 = 0.0306). Direct bilirubin and albumin are potential critical factors affecting early complications after liver transplantation. Close monitoring of these markers within 24-72 postoperative hours may help predict the occurrence of complications.