Sultan of Brunei Darussalam Haji Hassanal Bolkiah left Dhaka for his country by a special VVIP flight on Monday morning, reports news agency UNB.
Foreign minister AK Abdul Momen saw him off at Hazrat Shahjalal International Airport.
He also handed over an album to the Sultan containing photos of his two-day state visit.
The Sultan arrived in Bangladesh on Saturday afternoon and held meetings with president Abdul Hamid and prime minister Sheikh Hasina on Saturday and Sunday respectively.
The two countries signed four bilateral cooperation documents including a memorandum of understanding (MoU) on energy cooperation after his official talks with Prime Minister Sheikh Hasina on Sunday.