Résumé : Background: Although reproducibility studies are missing, a lymphoscintigraphic evaluation of the upper limb is often used in routine practice to diagnose lymphedema and in clinical research, for example, to investigate the effect of a physical treatment. Therefore, the aim of the present study was to investigate the reproducibility of the lymphoscintigraphic evaluation of the upper limb. Methods and Results: In breast cancer patients, 20 lymphoscintigraphic evaluations of the upper limb were performed on two test occasions with an interval of 1 week. 99mTc nanocol was injected subcutaneously in the hand. A standardized protocol was applied. In the early phase, two static images of the injection places were taken and in between dynamic images of both axilla during 40min (15min rest, 15min squeezing a ball, and 15min rest). After a break of 70min, a static image of the injection places and of the axilla was made. At the end, a partial whole body image was acquired. A strong reproducibility was found for the following quantitative variables (ICC 0.75 to 0.85): change of uptake in axilla during the break; change of extraction from hands during the break; and extraction and uptake in the late phase. The other quantitative variables (i.e., extraction form the hands in the early phase, time of arrival, accumulation rate, and uptake in axilla in the early phase) had weak to moderatie reproducibility (ICC 0.07 to 0.70). All qualitative variables (i.e., number of lymph nodes in the axilla, upper arm and elbow/lower arm, gradation of lymph collectors in upper or lower arm and of dermal backflow, and presence of lymph collaterals) had strong to very strong reproducibility (ICC 0.76 to 1.00). Conclusion: A lymphoscintigraphy of the upper limb is a reproducible imaging tool to assess lymph transport quantitatively and qualitatively.