The aim of this study was to investigate the incidence of insomnia in obstructive Sleep Apnea and Hypopnea Syndrome (OSAHS), as well as the impact of the comorbidity of insomnia and OSAHS on quality of life, sleep quality, and emotion. One hundred twenty-three patients with OSAHS, successively selected from May 2013 to December 2014, were assigned to the OSAHS group, and 52 age-matched subjects without OSAHS were assigned to the control group. The two groups were further divided by presence of insomnia, and the general characteristics, comorbidities, and quality of life were compared between the insomnia group and the non-insomnia group of patients with OSAHS. Hypertension (P=0.007), cerebral infarction (P=0.002), female sex (P=0.008), and senior age (P=0.002) were identified as risk factors for OSAHS with insomnia (P<0.05). The scores of the Pittsburgh Sleep Quality Index (P<0.001; 8.14 ± 3.20 vs. 5.19 ± 2.57) and the Depression Anxiety Stress Scale (P<0.05; 10.96 ± 5.25 vs. 9.09 ± 3.52) of patients with OSAHS and insomnia were higher than those of patients with OSAHS alone. The score of the healthy quality of life questionnaire (SF-12) was lower in patients with OSAHS and insomnia than in patients with OSAHS alone (P<0.001; SF-12 physiological score: 48.53 ± 3.68 vs. 54.25 ± 2.94; SF-12 mental score: 49.50 ± 3.40 vs. 53.19 ± 3.96). These results reveal that the incidence of insomnia in patients with OSAHS is significantly higher than in controls, cerebral infarction is a newly identified risk factor for insomnia in OSAHS patients, and OSAHS combined with insomnia significantly lowers quality of life compared with OSAHS alone.