Ahmed A. Khan, a Canadian Science Fiction writer and who was also the co-editor of the Anthology A Mosque Amongst the Stars with me has an article on what constitutes Islamic Science Fiction. Here is his definition of Islamic Science Fiction.
Islamic SF would be any speculative story that is positively informed by Islamic beliefs and practices. Below is a partial list of what we could consider as Islamic SF:
1. Any speculative story that strives to state the existence of the One God as described above.
2. Any speculative story that exhorts universal virtues and/or denigrates universal vices.
3. Any speculative story that deals in a positive way with any aspect of Islamic practices, like hijab, fasting, etc.
4. Any speculative story that features a Muslim as one of its main characters and the actions of this Muslim in the story reflect Islamic values.
5. Any speculative story which takes on one or more elements from the Qur’an or the teachings of the Messenger of Allah, Muhammad (peace and blessings be upon him), in a positive way.
The complete article can be read at the following URL: