Abstract: A device is provided for taking samples of a pressurized gas or liquid product, comprising a first through flow duct for the product to be sampled, a second through flow duct for a carrier gas or liquid, a communication conduit between said two ducts and a controllable means for normally closing and temporarily opening said communication passage. For injecting and vaporizing a liquid in analysis circuit, the device further comprises means for heating at least the downstream part of said communication conduit, i.e. that by which this latter is connected to said second duct through which said carrier gas or liquid flows.