The practical application of luteolin in food systems faces challenges due to its inherent instability. This study aimed to develop luteolin-loaded liposomes coated with whey protein isolate (WPI) to enhance the thermal stability and antioxidant activity of luteolin. The physical characteristics of both luteolin-loaded liposomes (LUT-Lips) and WPI-coated luteolin-loaded liposomes (WPI-LUT-Lips) were assessed. At a 5% WPI concentration, WPI-LUT-Lips demonstrated excellent dispersibility and improved encapsulation efficiency. WPI interacted with the liposome membrane via hydrophobic forces, hydrogen bonding, and electrostatic contact force, resulting in an efficient coating. Differential scanning calorimetry confirmed that WPI-LUT-Lips exhibited greater thermal stability compared to LUT-Lips, attributed to the protective effect of the WPI. Furthermore, WPI-LUT-Lips displayed superior antioxidant activity, as evidenced by their DPPH scavenging activity (86.36 ± 1.95%), TBARS reduction (25.33 ± 1.90%), and reducing power (82.86 ± 1.42%). Therefore, WPI-coated luteolin-loaded liposomes offer a promising way to enhance luteolin’s integration into food systems.