This study examined the effect of hair covering on hearing aid directional microphone performance. Nine adult, experienced hearing aid users (3 males, 6 females; mean age = 64.6 years) with mild to severe, sloping symmetrical sensorineural hearing loss were included in this study. Binaural Oticon Opn 1 receiver-in-the-ear hearing aids with closed domes were used to provide the recommended amplification for each participant. Speech Reception Threshold (dB SNR required for 50% speech understanding) was measured in all combinations of directional microphone (on/off) and hair covering (with/without) resulting in a total of four conditions. Results showed that directional microphones significantly improved speech understanding in noise (F(1,8)=15.51; p=0.004). However, there was no significant effect of hair covering in this small sample size of nine participants (F(1,8)=0.213; p=0.657). A pairwise comparison with Bonferroni corrections (α = 0.025) did not yield any difference between the two hair covering conditions (with and without) when the hearing aid was worn in the directional microphone mode (p=0.77). There was a large intersubject variability noticed in this small sample size