The organization of the French ministry of agriculture has changed and its position is regularly challenged. It has to increasingly share its traditional fields of competence with other bureaucratic organizations. Nevertheless it remains a specialized administrative apparatus with its own representation in the government. Besides, some patterns have remained surprisingly stable in its general organization. The French ministry of agriculture is organized in a few general directorates that are divided in a succession of smaller interlocked components, until the smaller one: the unit. Among them, the plant protection department has a specific trajectory that is mostly unknown. It was created at the beginning of the XXe century as a multi-site organization located in Paris and each region. Its position is never completely secured but it has been strengthened step by step, through administrative decisions that contributed to make the management of plant protection a need to secure national food production. We would like to propose an insight in the history of the French ministry of agriculture by presenting a sociohistory of one of its component: the plant protection department. For that, we will go back to before the department was set up, at the end of the XIXth century, when managing plant protection became an obligation for states through international conventions. We will describe how the plant protection department was created in France in this context.