Objective: This study aimed to evaluate the differences between Alzheimer's disease (AD) patients and controls in biochemistry and peripheral hemogram parameters neutrophil, lymphocyte, monocyte, platelet, and C-reactive protein (CRP) levels, lipid profile, inflammatory burden index (IBI), and hemoglobin, albumin, lymphocyte, and platelet (HALP) score and the relationship between inflammatory and immunonutritive biomarkers and cognitive impairment in patients. Method: Data from 79 patients with AD and 42 controls were included in the study. Medical data of the participants were obtained from hospital records. IBI was obtained by using the following formula: CRP x neutrophil/lymphocyte. HALP score was calculated as (hemoglobin (g/L) x albumin (g/L) x lymphocytes (/L))/platelets (/L). Results: Neutrophil count (p=0.003, effect size=0.60), CRP level (p<0.001, effect size=0.87), and IBI (p<0.001, effect size=0.93) were significantly higher in AD patients compared to the control group; hemoglobin (p<0.001, effect size=1.03), lymphocyte count (p<0.001, effect size=0.78), albumin level (p<0.001, effect size=1.31), and HALP score (p<0.001, effect size=0.85) were lower. According to the Standardized Mini Mental Test (SMMT) score, neutrophil count (p=0.001), CRP (p<0.001), and IBI (p<0.001) were significantly higher and lymphocyte count (p=0.001) and HALP score (p<0.001) were lower in the group with severe cognitive impairment. Albumin levels were highest in the group with mild cognitive impairment. In the patient group, there was a moderately significant negative relationship between SMMT score and age (p<0.001, r=-0.437), neutrophil count (p=0.033, r=-0.240), CRP (p<0.001, r=-0.451), and IBI (p<0.001, r=0.538). Lymphocyte count (p<0.001, r=0.412), high-density lipoprotein (HDL) (p=0.049, r=0.223), albumin levels (p=0.001, r=0.357), and HALP score (p<0.001, r=0.486) were moderately positively associated with SMMT score. Age ((3=-0.437, (3=-0.437, p<0.001), HALP score ((3=0.403, (3=0.403, p<0.001), and IBI ((3=-0.322, (3=-0.322, p=0.004) were found to be predictors for the severity of cognitive impairment. Conclusion: Our results revealed that inflammation and immunonutritive status play an important role in the pathogenesis of AD. Novel inflammatory and immunonutritive biomarkers, and IBI and HALP score may be promising clinical tools that may pave the way for more personalized treatment strategies and interventions for patients.