This study aims to describe the distribution characteristics of voriconazole (VRC) plasma trough concentrations (
C
trough
) in patients with liver dysfunction, identify factors influencing VRC
C
trough
, and provide recommendations for the use of VRC in this population. We retrospectively collected medical records of hospitalized patients with liver dysfunction who used VRC and underwent therapeutic drug monitoring (TDM) at the First Hospital of Changsha. The severity of liver dysfunction was assessed by the Child–Pugh (CP) score. Multiple linear regression was employed to explore factors affecting VRC
C
trough
in these patients. A total of 147
C
trough
from 102 patients with liver dysfunction were analyzed. Patients were categorized into a control group (
n
= 40), CP-A (
n
= 39), CP-B (
n
= 11), and CP-C group (
n
= 12). The initial probability of target attainment of
C
trough
was 70.6%, with 6.9% of patients obtaining subtherapeutic
C
trough
and 22.5% obtaining supertherapeutic
C
trough
. The initial
C
trough
in CP-A and B were 5.05 (0.64–9.57) mg/L and 5.37 (0.26–10.01) mg/L, respectively, significantly higher than the control group (
P
= 0.021 and
P
= 0.010). The proportion of VRC
C
trough
of >5.5 mg/L in CP-A and B was 33.3% and 45.5%, respectively. Multiple linear regression analysis revealed that factors such as age ≥70 years, CP class, C-reactive protein (CRP), and direct bilirubin were significantly related to the initial VRC
C
trough
. Among all measurements, patients with severe inflammation (CRP >100 mg/L), aged ≥70 years, and albumin levels of <30 or <25 g/L had significantly higher VRC
C
trough
. The treatment success rate of VRC was 69.6% (71 of 102), and the rate of VRC-related adverse drug reactions was 29.4% (30 of 102). The recommended half-maintenance dose may lead to elevated VRC
C
trough
in patients with CP-A and CP-B. TDM is essential for patients with advanced age, severe infections, or hypoalbuminemia to prevent excessive VRC trough levels.