The study examines the marketing efficiency of bananas in Yenagoa Metropolis of Bayelsa State, Nigeria. The objectives were to describe the socio-economic characteristics of banana marketers; determine the marketing margin and efficiency of banana marketers; identify marketing channels of bananas; and identify the constraints associated with banana marketers in the study area. Ninety (90) questionnaires were retrieved and used for the analysis out of the one hundred and four (104) questionnaires distributed to the banana marketers selected through a multistage random sampling technique from eight (8) markets in Yenagoa Metropolis of Bayelsa State using a structured questionnaire. Descriptive Statistics and marketing margin and efficiency formulas were used to analyse the data. The result showed that banana marketers were predominantly female. Budgetary analysis showed marketing efficiency greater than one which indicated profitability of the market. The Likert type showed the constraints, which significantly affect banana marketing as high perishability (3.88), high cost of transportation (2.98), inadequate market information (2.85) and heavy imposition of tax/levies (2.63). The study, therefore, recommends that Marketers should be encouraged to have market informants that will inform them of the increase or decrease in the prices of bananas in different markets in the study area.