Fibromyalgia is a chronic disease that causes muscle pain and fatigue. Our objective was to determine whether Whole Body Cryotherapy (WBC) can result in improved functional status and pain in fibromyalgia patients. It was hypothesized that positive effects will be realized due to the cold-induced modulation of the inflammation-immune axis.This present study is a randomized controlled trial with one between-subject factor (WBC group vs. Control group) and one within-subject factor (measurement point with 4 levels: pre-study, J8, 2 weeks later, 1 month later). Several parameters assessing pain intensity and functional status were measured repeatedly. In the WBC group, 10 cryostimulation sessions were performed (in addition to usual care) in a two-stage cryogenic chamber over a duration of 8 days. Duration of each cold exposure session was set to 3minutes at a temperature of −110°C. Subjects in the control group did not receive this intervention, and changed nothing in their everyday activities. Our primary study outcome measurement was recalled pain intensity over the last 7 days.A convenience sample of 28 patients (Mage=52.4±10.3 yrs old; 75% females) with fibromyalgia diagnosis were randomized (WBC, control). In pretest, the usual pain scores were respectively 7.50±1.81 for the experimental group (WBC) and 5.92±1.75 for the control group. It was a usual pain reduction at j8, 2 weeks and 1 month with respectively 4.88±2.98 (P<0.001), 3.13±2.40 (P<0.001), 3.25±2.92 (P<0.001) for WBC compared between 6.00±1.47 and 5.62±1.66 for control group. It was no change in the control group, WBC patients reported significant improvements on all secondary outcome measures (decreased disability/improved functional mobility).Patients with fibromyalgia were improved for pain and functional mobility after 10 whole-body cryostimulation (WBC) sessions compared the outcomes in the control group.