To provide a fluid control device achieving enhancement of the degree of integration and reduction in the number of components, and eliminating restrictions on the freedom in combination of fluid control instruments.

The fluid control devices 2-7 are provided with control device bodies 21, 31, 41, 61, 71 and joint portions 22, 32, 42, 62, 72 which have protuberances 22A, 22B..., 72A, 72B projecting in the front and back direction of the array beyond the control device bodies. The joint portions are disposed so that the protuberances of the adjacent joint portions overlap up and down and alternatively up and down along the array direction. Upper joint portions are provided with upper flow passages 25A, 25B, 42A, 42B getting into fluid communication with the control device bodies and opened to the lower surface of the protuberances. Lower joint portions are provided with lower flow passages 35A, 35B, 75A, 75B getting into fluid communication with the control device bodies and opened to the upper surface of the protuberances. The protuberances of the upper joint portions are disposed to overlap the protuberances of the lower joint portions, and the upper joint portions are detachably connected to the lower joint portions.