Background and Objectives: To investigate whether optical coherence tomography (OCT) could be utilized to characterize blood flow and vessel dimensions of facial telangiectasias before and during consecutive intense pulsed light (IPL) treatment. Study Design/Materials and methods: Dynamic OCT (D-OCT) was used to image telangiectasia immediately before and after, 1–3 days after, and 1 month after IPL treatment. Measurements included vessel width and depth, blood flow, and attenuation. Vessel dimensions at baseline were verified by a blinded observer. Clinical improvement was detected as good, moderate, or none, and adverse effects were registered at 1-month follow-up. Results: In total, 14 patients with facial telangiectasia were included. At baseline, vessel width was median 0.25 mm (interquartile range [IQR]: 0.19–0.34 mm) with an intra-class coefficient (ICC) of 0.89 (95% confidence interval [CI]: 0.70; 0.97). Vessel depth was 0.30 mm (IQR: 0.25–0.33 mm; ICC: 0.40 [CI: −0.07; 0.75]). Vessel depth increased significantly from baseline to 1-month follow-up (P = 0.008), whereas no significant changes in vessel width, blood flow, or attenuation were detected. Clinical efficacy seemed related to the relation between vessel dimensions and applied energy settings. Conclusions: The D-OCT imaging technique demonstrated that facial telangiectasias were found deeper within the skin after one IPL treatment. By characterizing the vessel dimensions and blood flow of telangiectasia, D-OCT may improve efficacy and safety of IPL. Lasers Surg. Med.