Details about the arrest and the charges against Tithy Sarker, a third-year zoology student, were not immediately available.
Jishanul Haque, the senior assistant superintendent of police at the Criminal Investigation Department, said on Wednesday night that they would brief the media about her on Thursday.
A group of students protested on the campus in Dhaka on Oct 24 against Tithy’s alleged Facebook post defaming Islam.
Bangladesh Chhatra League leaders joined their rivals Jatiyatabadi Chhatra Dal and religion-based groups in the protests and demanded her punishment.
The university later suspended her and launched an investigation into her alleged social media post.
Her family on Oct 27 filed a general diary at Pallabi Police Station saying that she had gone missing.
In a previous police complaint, Tithy had alleged that her Facebook account had been hacked and the perpetrators had uploaded the post that stirred the protests.