Purpose The interaction between sleep and recovery is a fundamental issue for ultra-marathoners, especially after an ultra-trail, but literatures on this matter remains are scarce. The main objectives were (1) to describe sleep parameters during the nights following an ultra-endurance event in amateur trail runners, (2) to evaluate the recovery kinetics, and (3) to assess the relationship between sleep parameters and recovery. Methods Nineteen race finishers were tested daily, from 10 days before to 10 days after the Ultra-Trail du Mont-Blanc® (UTMB®). Hooper Index (HI) was used to assess recovery and sleep parameters (total sleep time, TST and wake after sleep onset, WASO) were monitored using a wrist-worn actigraph. Results HI was higher than baseline until day 5 after the race (P < 0.05) and younger athletes had a lower HI than older ones during the recovery period (P < 0.001). TST was not modified by the race, but there was a WASO peak on the second night after. Positive correlations were found between WASO and muscle soreness (P < 0.001) and between TST and HI (P < 0.05). Conclusions In conclusion, participants needed 6 days for recovery after UTMB® and younger runners seemed to recover faster than older ones. Post-race sleep quantity did not increase, but the second night was more fragmented, most likely due to muscle soreness. Correlations between sleep and recovery parameters highlighted the key role of sleep for recovery.