This study was carried out to determine the effect of Lead Toxicity on the Physiology (Hematological indices) of Albino Rats (Rattus norvegicus). Lead exposure remains a major environmental and public health concern due to its toxic effects on hematological and physiological functions. A total of forty-eight (48) Albino Rats were procured and divided into two experimental groups of twenty-four (24) Albino Rats per group. One group of rats was treated with lead in their drinking water while the other was treated with lead in their feed. Also, a common control group which was made of twelve rats. Each experimental group was made up of three treatments sub-group which consisted of different concentration levels of 50 mg/kg, 100 mg/kg and 150 mg/kg. A one-way ANOVA was conducted to examine the effect of lead toxicity on the hematological indices of albino rats. The results revealed that lead exposure produced statistically significant effects on all parameters measured Hemoglobin (F (2,4) = 49.14, p = 0.002), PCV (F(2,4) = 13.44, p = 0.017), WBC (F(2,4) = 29.62, p = 0.004), and RBC (F(2,4) = 21.06, p = 0.008). Post hoc analysis using the Tukey HSD test showed that for each of these indices, the Control group differed significantly from both the Low and High lead exposure groups (p < 0.05), indicating that lead toxicity markedly altered the hematological parameters. In particular, hemoglobin concentration, PCV, and RBC counts decreased with increasing lead exposure, while alterations in WBC counts suggested immune response activation associated with lead toxicity. However, the study was limited by the relatively small sample size and lack of biochemical oxidative stress marker assessment. The results underscore the need for regular monitoring of Hematological parameters in individuals exposed to lead.