Forced vital capacity (FVC), forced expiratory volume in one second (FEV1), forced expiratory ratio in the first second (FEV1% VC), forced expiratory flow between 200 and 1200 ml (FEF200-1200), and forced mid expiratory flow between 25% and 75% of FVC (FMF) were measured in 275 Libyan men ranging from 20 to 60 years. All values were lower with increasing age and, apart from FEV1% VC, were positively correlated with standing height. This study can be used as a source of reference for Libyan men.