Chemical pesticides are health hazards affecting the livelihood of those who are occupationally engaged in spraying farm fields. The objective of the study was to determine the extent of the hazard of chemical pesticide application by farm workers in selected farms. The major parameters used were measurements of lung function and respiratory symptoms. The design of the study was cross-sectional and was conducted in four state farms. Lung function and respiratory symptoms of 102 pesticide sprayers of state farms of Ethiopia and of 69 non-sprayers were assessed All data were analysed by decade age groups adjusting for smoking habits. The results of lung function and respiratory symptoms of 102 pesticide sprayers and of 69 non-sprayers are presented. The 15-24 years age group of pesticide sprayers had significantly reduced forced expiratory vital capacity (FVC) and forced expiratory volume in one second (FEV1), as compared to that of similar age group non-sprayers. Analysis of variance on FVC and FEV for the five predictors (age, height, weight, chest circumference and FFM) of the non-sprayers was highly significant (F = 4.647, 5.563 & P = 0.001, 0.000 for FVC and FEV1 respectively). 5.9% and 16.7% of the pesticide sprayers had symptoms of cough and breathlessness respectively. Pesticide applications resulted in reduced lung function and evoking respiratory symptoms. Pesticide sprayers need to be sensitised to the hazardous consequences of pesticide applications for human health and the environment and should be encouraged to wear personal protective devices during work on farms.