Police said that Ananta Bijoy Das was murdered in broad daylight as he headed to work at a local bank in the city of Sylhet.
A group of four masked men attacked Das on a busy street and then fled into the crowds.
The blogger suffered numerous wounds all over his body. He was rushed to hospital but was declared dead on arrival, according to medics.
Das was an activist for a group that demands a secular Bangladesh. He was the editor of a science-based magazine, and regularly contributed to Mukto Mona (free mind), a website advocating rationalism and opposing religious fundamentalism.
Its founder, US-based blogger Avijit Roy, was hacked to death in February.
On March 30, Washiqur Rahman, another secular blogger, was killed in similar manner in the capital, Dhaka.