Praise be to Allah.
Shaping the eyebrows by trimming, shaving or plucking their edges in order to appear beautiful, as is done by some women nowadays, is haraam because it involves changing the creation of Allaah and following the Shaytaan in his tempting of mankind to change the creation of Allaah. Allaah says (interpretation of the meaning):
“Verily! Allaah forgives not (the sin of) setting up partners in worship with Him, but He forgives whom He pleases sins other than that, and whoever sets up partners in worship with Allaah, has indeed strayed far away.
They (all those who worship others than Allaah) invoke nothing but female deities besides Him, and they invoke nothing but Shaytaan, a persistent rebel!
Allaah cursed him. And he [Shaytaan] said: ‘I will take an appointed portion of Your slaves;
Verily, I will mislead them, and surely, I will arouse in them false desires; and certainly, I will order them to slit the ears of cattle, and indeed I will order them to change the nature created by Allaah.’ And whoever takes Shaytaan as a wali (protector or helper) instead of Allaah, has surely suffered a manifest loss.”
In al-Saheeh, it was reported that Ibn Mas’ood (may Allaah be pleased with him) said: “Allaah has cursed the women who do tattoos and those who have this done, the women who pluck eyebrows and those who have this done, and the women who file their teeth and change the creation of Allaah.” Then he said: “Should I not curse those whom the Messenger of Allaah (peace and blessings of Allaah be upon him) cursed, when it says in the Qur’aan (interpretation of the meaning): ‘… And whatsoever the Messenger gives you, take it, and whatever he forbids you, abstain (from it)…’ [al-Hashr 59:7]”