Background: Welding is the most common way of permanently joining metal parts. Several metals commonly present in welding fumes, including Cr, Fe, Mn, Cd and Pb, are capable of generating reactive oxygen species (ROS) resulting in oxidative stress which inturn leading to disease development. Objectives: This study was carried out in one of Iron and steel industries to asses health hazards with special emphasis on respiratory symptoms among welders through monitoring the elevation of lead, manganese, iron, cadmium and chromium blood levels and the reduction of superoxide dismutase enzyme, as abiomarker to oxidative stress status, due to exposure to welding fumes, also clinical assesment and pulmonary function tests were done for the studied groups. Subjects and Methodology: The case-control study was carried out on two groups. The exposed group consisted of fifty male workers occupationally exposed to welding fumes of one of the private factories for Iron and Steel industry at El Asher Mn Ramadan,their mean age were from 20 to 55 years (34.3 ± 6.9 ), working on the basis of 12 hours/day with one day off per week, A control group of thirty males matched for age that ranged from 25 to 50 years (34.5 ± 5.8 ) sex, smoking habits, selected from relatives of the Kasr El Eini hospital patients, were also involved in our study. The following investigations were performed after taking individual consent: (A) All workers were interviewed using a special questionnaire including occupational history. (B) Ventilatory function tests were done measuring FVC, FEV1%, FEV1/FVC and PEF. (C) Determination of superoxide dismutase blood level (SOD). (D) Determination of chromium, cadmium, lead, manganese, iron levels in the blood samples. Results: The study revealed increased prevalence of respiratory symptoms among welders, most of them had decreased ventilatory functions parameters compared to unexposed group.The levels of investigated metals (manganese, lead, iron, cadmium and chromium) are statistically significantly higher in exposed welders and had statistically significantly lower levels of Superoxide dismutase compared to the control group. Recommendations: From the present study we recommend Prospective studies can use SOD as a screening test for assessing whether there is a need for further reduction of worker exposure to welding fumes or not.Pre-employment and Periodic medical examination for welders including clinical examination, pulmonary function tests and measuring the level of superoxide dismutase activity. Controlling the welding fumes and particulates by using good exhaust ventilation systems at the source of fumes. Personal protective clothes e.g. gloves and respiratory protective equipment should be used in welders. Health education programs of workers about hazards of exposure to harmful agents.