Maritime Guinea is a region that opens onto the Atlantic Ocean on about 300 km of coastline. This is characterized by the almost continuous formation of mangroves, estuaries and a nearby coastal strip. It is home to a rich biological diversity, with the presence of various species of fish, marine mammals, marine turtles, avifauna, etc. Its population is 3.7 million. The main socio-economic activities are fisheries, agriculture, shellfish harvesting, saliculture, mangrove logging, tourism, mining, etc. The Republic of Guinea has important mineral resources with about 40 billion tons of bauxite (the world's second largest producer), over 10 billion tons of iron, 40 million tons of limestone, and so on. The development of this rich mining potential requires the development of mineral ports likely to have repercussions, notably on the fish biodiversity on which the communities living in the coastal zone depend. Planning for development requires the adoption of an overall vision to make informed choices based on relevant decision criteria. A review of the literature, field observations, and interviews with all parties involved in the planning of mineral ports, led to identified the major issues and then structured them into criteria and indicators. Particular attention was paid to the consideration of fisheries biodiversity in the port planning decision-making process. These criteria can be used as part of a strategic environmental assessment (SEA) of management scenarios. This study made possible to construct, in a participative manner, twenty criteria and indicators of effects of strategic level structured according to the four main issues.