The present invention relates to a gas emission modeling device consisting of two lateral walls (1), (2), a front wall (3), featuring an outlet opening (4) of rectangular form, and a rear wall (5) with a round opening (15) accommodating and axial-flow fan (6). A top wall (7) is divided into 3 parts, which separate a tunnel interior, wherein a strip (09) with hooks (19) for attaching separated gas sensors and other instruments is situated in the first part (8), in the middle part (16), there is situated a slide-in transparent board (11) with a pin (12) attached thereto. A storage surface (14) for a substrate to be investigated and reaching up to the third part (13), is disposed underneath the middle part. The walls of the first part (8), the second part (16) and the third part (13) are thermally insulated.