We detected increased serum orexin A level in mild to moderate AIS patients with early onset of stroke‐related insomnia (33.44 vs 18.66 pg/ml, p = .004) as well as in patients with short‐term neurological improvement compared to those without improvement (31.78 vs 16.24 pg/ml, p = .038). Here, HCRT is linked to insomnia measurement.