The paper's broad objective is to facilitate the spatial integration of main foodstuffs' markets (plantain, cassava, onion, rice, etc.) in Cameroon where the authorities have set up an information system on markets (ISMS) to support the information flow on prices, as well as the correction of the market dysfunctions. Taking into consideration the particular case of the banana plantain, one would like to understand why the urban consumer prices do not cease increasing. Is it due to lack of arbitration or a bad information circulation between the consumption and the production markets? This study answered these questions via econometric time series models (VAR, ADL, ECM, AECM). Monthly prices of plantain in kilogrammes collected by the MINAGRI, the CARBAP and the DSCN on ten markets over the period 1993 to 2000 were used. Results showed a weak integration of the production to the consumption markets. In other words, the urban consumer prices increase because, in part, there is a bad information circulation in the various markets. The concentration of information in the hands of certain tradesmen, in particular the wholesalers, caused an asymmetry of the price information between the consumption and production markets. This asymmetry of price information prevented other wholesalers from penetrating the plantain marketing chain. This resulted in a weak supply of cities and consequently a high price of plantain to the consumers. To maintain urban food security in plantain, attempts must be made to cancel the information asymmetry in the prices between consumption and production areas.