In order to determine the effectiveness of the agricultural extension staff working in public, a survey was carried out on 131 extension staff employed in the counties and centre of Erzurum city. The data obtained from the survey was analyzed using OLS (ordinary least squares) model in GRETL software. The number of days an extension personnel spends on the land on a monthly base and the average number of farmers interviewed for training purposes were taken as dependent variables to indicate the effectiveness of extension staff. In addition, the factors which were influential on these variables were determined. As a result of the analyses, the following issues were found to be influential on the effectiveness of the extension practices of the extension staff working in the public institutions: regional differences; the age, the marital status, the graduation date of the extension member; whether the member received an extension education; whether the member thought the job he/she was carrying out was appropriate for his/her specialty; the number of the villages served; and whether the member received an in service training. It was concluded that the extension staff employed in public institutions should receive in service training periodically on a constant base, studies should be carried out to limit the number of farmers and the villages an extension member is in charge of, the extension staff should be employed in fields appropriate for their specialty and that they should receive adequate training in agricultural extension regardless of their specialty.