Objective To investigate the improvement effect of intense pulsed light (IPL) combined with hyaluronic acid (HA) injection on skin elasticity and pore enlargement in patients with facial fine lines. Methods A total of 60 patients with facial fine lines admitted to Aviation General Hospital from January 2022 to December 2025 were selected, and they were divided into the control group and the observation group by the random number table method, with 30 patients in each group. The control group received IPL monotherapy, and the observation group received additional HA injection on the basis of the control group. The skin elasticity, pore enlargement, skin barrier function, dermal structure and fine line parameters were compared between the two groups. Results After treatment, the R2, R5, and R7 values in the two groups were higher than those before treatment, and those in the observation group were higher than those in the control group (P <0.05). After treatment, the percentage of pore area, pore count and mean pore diameter in the two groups were lower than those before treatment, and those in the observation group were lower than those in the control group (P <0.05). After treatment, the TEWL in the two groups was lower than that before treatment, and that in the observation group was lower than that in the control group (P <0.05). After treatment, the stratum corneum hydration and sebum content in the two groups were higher than those before treatment, and those in the observation group were higher than those in the control group (P <0.05). After treatment, the dermal thickness and skin gloss in the two groups were higher than those beforetreatment, and those in the observation group were higher than those in the control group (P <0.05). After treatment, the percentage of fine line area in the two groups was lower than that before treatment, and that in the observation group was lower than that in the control group (P <0.05). Conclusion The combination of IPL and HA injection can synergistically improve skin elasticity and reduce pore size in patients with facial fine lines, effectively repair skin barrier function, thicken the dermal structure, and reduce the appearance of fine lines. The overall therapeutic efficacy is superior to that of IPL monotherapy.