The indoor background ionizing radiation of various offices of the various departments in Federal University of Technology, Owerri (FUTO) was estimated in this study. This was conducted using a well calibrated digital Geiger -Muller Counter (GCA -04W). The highest value measured was 0.0873 ± 0.1432 µSv/h while the lowest value was 0.0006 ± 0.0001 µSv/h with an average value of 0.0052 ± 0.0013 µSv/h. The average value of the estimated absorbed dose rate for all the departments and annual effective dose equivalent (AEDE) was 4.549 ± 12.047 nGy/h and 22.313 ± 59.092 µSv/y, respectively. For the Excess Lifetime Cancer Risk (ELCR), the average value for the departments was found to be 0.061 ± 0.162. The results of this study show that the level of BIR in all the departments was lower than the world average. In general, it can be concluded that FUTO is relatively safe from the health hazards posed by BIR.