Objective To investigate the shift patterns and occupational fatigue among intensive care units (ICU) nurses and to analyze the correlation between them. Methods A total of 498 ICU nurses from 6 comprehensive tertiary hospitals in eastern, central and western regions of China were conveniently selected, and a cross-sectional survey was conducted using a general information questionnaire, the Occupational Fatigue Exhaustion/Recovery Scale and the Pittsburgh Sleep Quality Index. Results The scores of occupational fatigue among ICU nurses were as follows: chronic fatigue 50.00(33.33,66.67), acute fatigue 63.33(46.67,76.67) and intershift recovery 46.67(36.67,56.67). Multiple hierarchical linear regression showed that after controlling for individual characteristics, compared with the shift pattern of "8h day shift-8h evening shift-8h night shift-off-off", those with the shift pattern of "12h day shift-12h night shift-off-off" had higher chronic fatigue levels (P<0.05) and those with the shift pattern of "8h day shift-8h night shift-8h evening shift-off-off" had lower levels of intershiftrecovery (P<0.05), but there was no significant difference between shift patterns and acute fatigue levels of ICU nurses (all P>0.05). Conclusion The chronic fatigue and acute fatigue of ICU nurses are at moderate and above levels, and the intershift recovery ia at a moderate or low level. Shift patterns are associated with occupational fatigue levels of ICU nurses, and nursing managers could consider improving occupational fatigue by optimizing nurses′ shift patterns.