Fatimiyya (Arabic: فاطمیة) are days in which Shia Muslims mourn the martyrdom of Fatimah, daughter of the Islamic prophet Muhammad.

[6] Whilst there is no established convention, periods of Fatimiyya such as "the first ten days" (10–20 Jumada al-Awwal) or "the second ten days" (1–10 Jumada al-Thani) are in recent years increasingly commemorated by Shia Muslims much like the first ten days of Muharram, which are traditionally associated with the martyrdom of Husayn.

The prominent place of Fatimah in Islam as daughter of Islamic prophet Muhammad, the hardships she endured in her short life, and that she gave her life to defend the first Shia Imam, Ali, are among the reasons Shia Muslims give for the annual remembrance of Fatimah.

[7][8] Apart from Iran and Iraq, Fatimiyya is also observed in other countries, including India, Pakistan,[9] Australia,[10] Azerbaijan, and Tajikistan.

[13] The uncertainty about when Fatimah died is often attributed to multiple factors: