Asif Mohiuddin, 29, was attacked on Monday night by three unidentified men near his office in Dhaka's upscale Uttara district.
"We operated on him for more than three hours. He is improving but still not out of danger. He has six deep cuts including two grave ones in the shoulder," Haridas Saha, a surgeon at Dhaka Medical College Hospital, told AFP.
"The nature of the cuts proved that the attackers wanted to murder him," Saha said, adding that friends of Mohiuddin who were with him at the time of the attack blamed Islamic "fundamentalists".
Local police chief Rezaul Islam confirmed the attack but did not comment on the motive.
"The attackers were lurking near his office. He was attacked as he was about to enter the office. Passers-by rushed him to a hospital," Islam told AFP, adding police were investigating the motive.