The study was conducted with the objective of identifying honeybee poisoning plant, assessing the status of agro-chemicals utilization and to determine the toxicity effects on Apis mellifera scutllata in Sidama zone, Southern Ethiopia. Semi-Structured questionnaires were developed and 160 individuals (80 beekeepers and 80 non beekeeprs) were interviewed on voluntary basis. The result of this assessment indicated that 75 (93.75%) of beekeepers complained presence of plant poisoning on honeybees in the study area. Ten plants were complained having poisoning effect on honeybees by beekeepers in the study area. Among these plants Lanthana camara, Euphorbia continifolia, Climatis flammula, Ranclus multifides, Discopdium penninervium, Climatisinte grifolia, Datura metal linn, Sesbania sesban , Phytolaca americana and Justitia schemperina, were the most frequently complained toxic plants in the study area. Seven different agro-chemicals (2,4-D, Agrothoate 40% Malathion 50%, pyriban48%, Diazinon 60%, Macozeb 80% and Pallas 45 OD) were commonly applied on various crop in the study area. The main sources of these agro-chemicals are cooperative, legal and illegal traders. 95% of farmers used empty containers for household purpose. 3.25% of the respondents left in farm while 1.25% of the respondents indicated that they have burnt. Most of agro-chemical users (80%) of the respondents had no training on how to apply Agro-chemicals safely to honeybees, themselves and environment and 97.5 % of respondents applied agro-chemicals without following the recommended instructions in addition 95.62% of the respondents did not use protective clothes when spraying. Acute toxicity analysis in the laboratory indicated that all tested agro-chemicals were found significantly toxic to A.m.scuttlata compared to negative control via feeding. Agrothoate 40%, Malathion50% EC and Dianznon 60% were highly toxic with 100% of experimental bee mortality, less than an hour. All agro-chemicals were statically significant toxic to honeybee when compared (P<0.01) standard insecticides and control group through all exposure rout. Therefore, further study on complained poisonous plants and toxic chemicals in the study area, and proper utilization agro-chemicals are important to minimize poisoning of honeybee. Keywords; Agro-chemicals, Toxicity effect, Honeybee poison plants, Sidama zone