Abstract
The objective of this study was to estimate the total count of airborne fungi indoors and outdoors in three largest provinces of eastern region of Saudi Arabia. Seasonal variation on the fungi total count and fungi diversity was studied. This study has been carried out by the settling plate technique for a period of 1 year. Samples were collected once in each season. A total of 30 fungi species belonging to 18 genera were isolated. Aspergillus sp. and Cladosporium sp. were the two dominant fungi genera indoors and outdoors. The total fungi count in indoors was less than that of the outdoors. There was seasonal variation in the total count and diversity of the airborne fungi. Fungi diversity was higher in spring indoors and outdoors. Fungi total count in Qatif was the highest then Dammam and then Khobar in indoors, whereas the Dammam was the highest then Khobar and then Qatif in outdoors.