Most of the studies assessed the effect of Pb-exposure on serum total calcium and phosphorus. This study assessed the effect of Pb-exposure on serum total calcium (TCa2+) and phosphorus (P) components such as corrected calcium (CCa2+), ionized calcium (ICa2+), percentage of ICa2+from TCa2+, percentage of ICa2+from CCa2+, ratios of TCa2+: P, CCa2+: P, ICa2+: P and product of Ca2+ and P in workers of different category of Pb-exposure. This study enrolled 176 male Pb-exposed workers and categorized into two groups based on blood lead levels (BLLs) recommended by BEI-ACGIH. The low Pb-exposure group is 86 workers with their BLLs is ≤ 30 μ g/dL and high Pb-exposure is 90 workers with their BLLs is > 30 μ g/dL). 80 healthy workers with no occupational exposure to Pb were included them as control for the comparison. The serum calcium, phosphorus and albumin concentrations were done by using diagnostic kit methods. BLLs were estimated by using the flame atomic absorption spectrometric method. The serum TCa2+, CCa2+ and ICa2+ were significantly decreased in low and high Pb-exposure groups as compared to control. The ratios of TCa2+: P, CCa2+: P, ICa2+: P was significantly decreased in the high Pb-exposure as compared to low Pb– exposure and controls. Product of TCa2+X P was significantly increased in the high Pb-exposure group as compared to low Pb-exposure. A negative association was noted between BLLs and serum TCa2+, ICa2+and CCa2+ in a high Pb-exposure group. The components of serum calcium and phosphorus were significantly altered in Pb-exposed workers.