Abstract: Microphone windscreens, pivotal in acoustic detection systems, serve to mitigate wind noise interference in outdoor testing, ensuring accurate and reliable data. The windproof efficacy of these windscreens is critical to test outcomes. This study focuses on the methodologies for assessing windscreen windproof performance and the factors influencing these results. The windscreen's windproof capability is quantified using the 1/3 octave frequency difference pre- and post-windscreen application at a constant wind speed. The impacts of measuring point position and background noise on windproof performance are explored. Results reveal that the turbulence increase at the flow field edge leads to test results at the wind tunnel inlet's edge being 2.0 to 32.8 dB higher than those in the central region. Thus, it is advisable to avoid the tunnel inlet's edge for test positioning. Additionally, altering the wind tunnel's background noise with sound sources demonstrated that test outcomes remain unaffected by background noise if the 1/3 octave band sound pressure level is at least 7 dB lower than the measurement band's sound pressure level. Consequently, to determine if background noise meets testing standards, the 1/3 octave band sound pressure level should be used, ensuring it is at least 7 dB lower than the measured band's level.