The objectives of this research were to study the knowledge and attitude of designated district personnel toward delegated authority according to Food Act B.E. 2522 and to study the relationships between knowledge and attitude. The sample group consisted of 285 officials from designated district personnel in central region who have positions as district or subdistrict public health officers, head pharmacists in community hospitals, head pharmacists in general hospital which there wasnt settlement of community hospital and pharmacists. the subject were guestioned on their Knowledge of and attitude towards the ministry declaration of public health 141(B.E. 2535 ) concerning the adjust designated personnel for practice to Food Act B.E.2522. The instrument used in this study was a questionnaire. The results were as follows. It was found that designated district personnel Knowledge was inversely related to age, period of working, work experience. Statistically significant differences in knowledge at the 0.05 level were found according to sex, status, level of education, position and training. Attitude of designated district personnel toward delegated authority according to Food Act B.E. 2522 was directly related to age, period of working and work experience. There were statistically significant difference at the 0.05 level according to sex, health of consumer agency. There was negative relation between knowledge and attitude on the designated district personnel toward delegated authority according to Food Act B.E.2522. There was a statistically significant difference at the 0.05 level. Due to differences between the Knowledge of Pharmacist and District or subdistrict public health officers, It was recommended that proper courses of training be developed for the two groups seperately.