Background and Objective: While insufficient sleep remains an under-recognized public health issue across the globe, there is paucity and heterogeneity of data regarding its cardiometabolic and haemoinflammatory implications. We, therefore, aimed to evaluate the impact of chronic sleep restriction on cardiometabolic and haemoinflammatory parameters in rats. Materials and Methods: 16 male Wistar rats (aged 8-10 weeks) were randomly assigned into equal control or sleep restriction groups. Gentle handling was used to induce sleep restriction for six weeks. Fasting weight and blood sugar were obtained and lipids were analyzed using their respective Randox kits. Malondialdehyde (MDA) levels and catalase (CAT) and superoxide dismutase (SOD) activities were assayed. Full blood count and CD4+ T cell count were determined using automated analyzer. Data were analyzed using Student’s t-test, with level of significance set at P ≤ 0.05, via SPSS software. Results: Chronic sleep restriction caused significant initial weight loss, increase in feed consumption, and percentage increase in fasting blood sugar (FBS) (32% vs. 15%). We also noted the triglyceride-glucose (TyG) index of sleep-restricted rats to be significantly higher (6.22) than that of controls (5.62). In addition, a significant reduction in monocyte count, monocyte-lymphocyte ratio (MLR), and absolute CD4+ cell count among the sleep-restricted rats was observed. Conclusion: Our findings have provided objective evidence that, over the course of 6 weeks, 5 hours of sleep restriction had caused body weight gain, hyperglycaemia, insulin resistance, and impairment in immunoinflammatory status; hence, it could be a risk factor for developing cardiometabolic syndrome and immune-related disorders.