Objective Gingival crevicular fluid (GCF) analysis of various inflammatory mediators has been investigated as a means of providing objective criteria of peri-implanttissue health. In this report, the crevicularfluid levels of interleukin-8(IL-8), GCF volume and clinical parameters were studied.Methods GCFwas sampled from 35 healthy and 35 inflamed sites of implan- tation patients. IL-8 levelswere analysed using ABC-ELISA. Clinical parameterswere measured, and data analysiswas performed using the software package SPSS10.0.Results Significant difference was observed between healthy implant sites and peri-im- plantitis sites. GCF volumewas positively correlatedwith PD, PI, GI andMOB. The total amount of IL-8 was positively correlated with PD and GI.Conclusion This investigation suggested thatGCF volume and IL-8 cytokine may be of value as a diagnostic and prognostic marker for peri-implantitis.