Purpose: This investigation aimed to evaluate the effects of wearing upper- and lower-body compression garments on cross-country (XC) skiing performance in elite winter biathletes. Methods: Seven senior biathletes (four males, three females) from the Swedish national team performed two exercise trials in a randomized and counterbalanced order, wearing either commercially-available upper- and lower-body compression garments (COMP) or a standard winter-biathlon racing suit (CON). In each trial the athletes roller-skied on a customized treadmill, completing a time-trial (TT) simulating the skiing duration of a biathlon sprint race, followed by a time-to-exhaustion (TTE) test designed to elicit exhaustion within ~ 60–90 s. Heart rate (HR), blood lactate concentration (BLa), rating of perceived exertion (RPE), thermal sensation (TS) and thermal comfort (TC) were monitored throughout each trial, while muscle soreness was measured up to 48 h after each trial. Results: Pressure exerted by the clothing was significantly higher at all anatomical sites for COMP compared to CON (P ≤ 0.002). Wearing COMP led to small positive effects on TT (d = 0.31) and TTE test (d = 0.31) performances compared to CON, but these differences were not statistically significant (P > 0.05). No significant differences were found for any physiological (HR or BLa) or subjective (RPE, TS, TC or muscle soreness) responses between COMP and CON (P > 0.05). Conclusions: Wearing COMP during maximal XC skiing may have small but worthwhile beneficial effects on performance for some individuals. Due to individual variation, athletes are advised to test COMP prior to competition.