This study was aimed at marketing chain of sesames in Gimbi Woredas of Oromia Region with specific objectives of identifying marketing channels and factors affecting outlet choice decisions of farm households. The data were collected from both primary and secondary sources. The primary data for this study were collected from 127 farmers, 17 traders and 22 consumers through application of appropriate statistical procedures. The study result showed that sesame producers are faced with lack of improved seed variety and high diseases and pests. On marketing side, limited access to market, low price of product, lack of storage, lack of transport and low quality of product are the major problems. The multinomial logit model results indicated that the probability to choose the collector outlet was significantly affected by Land, Market price of sesame, Membership to any Cooperatives, Credit Access, and Owning Transport Facility compared to wholesale outlet. Similarly, the probability of choosing cooperatives marketing outlet was affected by land and Quantity of sesame produced compared to wholesale outlet. Therefore, policy aiming at increasing farmers' access to modern inputs, developing and improving infrastructure, gender consideration, cooperative development and improving extension system are recommended to accelerate the chain's development.