Airbus has unveiled contracts worth $9.6bn with orders for 114 aircraft, while Boeing has announced orders worth $5.7bn for 28 aircraft.
The totals are an estimate of the value of each order based on the catalogue price of each aircraft.
The final value of the order will depend on price negotiations between the companies and their customers.
The total for Boeing excludes several orders that were announced by the group during the show but have already been included in the order book of the US company.
Among the largest orders were 40 Airbus A320 jets for Malaysia's AirAsia and 10 Boeing 747-8 cargo planes for Dubai's Emirates.
At the beginning of July Airbus said it had received 142 orders since the start of the year compared with 445 for Boeing over the same period.
The Farnborough air show began on Monday and ends on Sunday July 23.