Peri-implantitis is one of the leading causes of implant failure and loss, and its early diagnosis is not currently feasible due to the low sensitivity of currents methods. In the current exploratory cross-sectional study, we explored the diagnostic potential of lymphocyte B and Th17-chemotactic cytokine levels in peri-implant crevicular fluid (PICF) in 54 patients with healthy, peri-mucositis, or peri-implantitis implants. Peri-implant crevicular fluid was collected, and the levels of the molecules under study were quantified by Luminex assay. The concentrations of CCL-20 MIP-3 alpha, BAFF/BLYS, RANKL and OPG concentration in PICF were analyzed in the context of patient and clinical variables (smoking status, history of periodontitis, periodontal diagnosis, implant survival, suppuration, bleeding on probing, periodontal probing depth, clinical attachment level, mean of implant probing depth, and plaque index). Patients with peri-implantitis, appear to have an overregulation of the RANKL/BAFF-BLyS axis. This phenomenon needs to be investigated in depth in further studies with a larger sample size.