ICU survivors may experience various long-term sequelae, recognized as Post-Intensive Care Syndrome, that includes psychiatric symptoms: anxiety, depression, and post-traumatic stress disorders symptoms (PTSD). While it was hypothesized that an ICU diary could help patients after discharge, improving their hospitalization memories and quality of life, it is unclear whether it may reduce psychiatric disorders, in particular PTSD. We performed a qualitative exploration of survivors' subjective experience of their ICU stay, their representations, memories, meaning-making of their experience and use of their ICU diary. Five participants (ICU survivors, 3 men and 2 women, who received a diary) were included in this study. We conducted non-directive interviews 6 months after discharge. These interviews were transcribed and analyzed using Interpretative Phenomenological Analysis. Major recurring themes of discourse included: (1) The nightmare of the ICU experience: from an impression of vagueness to dispossession, (2) The positive image of health-care workers during intensive care, (3) The place of the relatives and health-care workers' writings in the diary: either a support or a barrier, (4) The difficult return back home, and daily life after intensive care. Participant's representation of their ICU experience seemed to reflect the meaning they had given it through their own reflections and that of health-care workers in the diary. For some participant, the diary was associated to the pain and strangeness of the ICU experience; therefore, their recovery required them to take some distance with it. The ICU diary allowed participants to construct their illness narratives, and to become aware of the presence and support of health-care workers. The diary was also perceived as the witness of a period they wished to forget. Trial registration: NCT02519725.