Almost 20 countries, including Iran, Singapore, Indonesia, Japan, Azerbaijan and Turkey are attending the event, IRNA wrote.
Pakistan's Provincial Minister for Culture and Tourism Sardar Ali Shah inaugurated the event at Karachi expo center.
A pavilion of about 60 square meters has been allocated to Iranian companies at the expo. A traditional musical band from Sistan-Baluchistan is also taking part in the exhibition.
The aim of the expo is to promote tourism in Pakistan and also allow other countries to make the visitors aware of their tourist attractions.
Three Iranian airlines including Iran Air and Mahan Air are taking part in the international tourism exhibition. A number of joint Iranian and Pakistani tourism companies are also participating in the event.
Iranian companies, which are taking part in the exhibition to promote tourism in Iran, are also interested in enhancing cooperation with their Pakistani counterparts to promote tourist activities in the two countries.