The invention concerns a device (20) for UV-spectrometric analysis of gaseous compounds, said device (20) comprising: a measurement channel (5) intended to accommodate a flow of sample gas to be analyzed, a window member (16) transparent for ultraviolet radiation arranged at a first end (5a) of the measurement channel (5), a radiation source (11) capable of generating ultraviolet radiation arranged to emit radiation through the window member (16) and into the measurement channel (5), and a spectrographic member (3) for measuring of ultraviolet radiation emitted by the radiation source (11) arranged at a second, opposite, end (5b) of the measurement channel (5), wherein the device (20) is arranged such that ultraviolet radiation entering the measurement channel (5) at the first end (5a) can propagate through the measurement channel (5), interact with the accommodated gas and be measured by the spectrographic member (3) at the second end (5b) of the measurement channel (5). The invention is characterized in that the first end (5a) of the measurement channel (5) is open towards the window member (16) and in that a channel (6, 18) for guiding a protection gas is arranged in connection to the window member (16) such that protection gas fed through the protection gas channel (6, 18) is allowed to flow over and cover the side of the window member (16) facing the measurement channel (5) and to flow further into the measurement channel (5).