This is a cross-sectional study aims to estimate the concentration of bio-aerosols in a manufacturing factory. There were 108 respondents involved with 100% response rate. Self-administered questionnaire was used to collect infor- mation on socio-demographical characteristics and work characteristics. IUALTD standardized questionnaire was used to measure respiratory symptoms among respondents. Duo Sas Super 360 was used to measure the concentra- tion of airborne bacteria and fungi. Twenty four air sampling was completed. Findings shows that only prayer room (650 cfu/m3) recorded to have bacteria concentration beyond the standard acceptable limit. The most prevalent reported respiratory symptoms were cough and phlegm (22.2%) followed by wheezing and chest tightness (20.4%). There were no significant association between socio-demographical factors, work factors and airborne bacteria and fungal concentration with respiratory symptoms. Better ventilation with regular cleaning of prayer cloth and carpet is warranted for the prayer room. Future study is recommended to include knowledge, attitude and practice related to hygiene among workers.