Purpose: Indocyanine green (ICG) fluorescence angiography is used to evaluate tissue perfusion in many different medical fields. This study aims to evaluate the value of ICG angiography in the determination of tissue perfusion in the PAD lower extremities. Material and methods: In a prospective clinical study, ICG angiography was used to evaluate tissue perfusion and collateralization in 30 PAD patients. The perfusion index and maximum fluorescence intensity (MPI) were calculated as arterial perfusion parameters. Results: Significant differences in the perfusion index were found for the different PAD stages (p < 0.001). Poor collateralization was associated with a significantly lower perfusion index than good collateralization (p = 0.003). A ROC analysis for the perfusion index showed a positive likelihood ratio of 6.00 and a negative likelihood ratio of 0.00 with an area under the curve of 0.949 to discriminate critical and non-critical PAD. Conclusion: ICG angiography is a promising diagnostic tool to quantify tissue perfusion and demonstrate critical limb ischemia and collateralization in lower extremities affected by PAD.