They were seized in a district 170 kilometres (105 miles) east of Quetta, the capital of sparsely populated Balochistan province, the official said.
"We have received reports that two Swiss nationals have been kidnapped in Loralai district," provincial home secretary Zafarullah Baloch told AFP."We have sent a team comprising police and an administration official to search them," he added.
Loralai's district police chief Ghulam Ali Lashari said officers had found couple's abandoned Volkswagen vehicle in Killi Nigah area.
The couple arrived at Sirki Jungle checkpoint at about 5.45 pm (1245 GMT), registered as Swiss tourists and were allowed to enter an area controlled by tribal police, Lashari said.
"According to witnesses when they were travelling in Killi Nigah area some unknown gunnies intercepted the Swiss couple and took them away to an unknown place," he said.
Baloch and Lashari said the pair had entered Balochistan from Dera Ghazi Khan district in Punjab province and might have been heading for Quetta.
No one has yet grabbed credit for the incident or contacted authorities about the kidnapped foreigners, he said.
Balochistan, which borders Iran and Afghanistan, has seen an upswing in violence recently, with the province suffering from a separatist insurgency, sectarian violence and Talibs.
Hundreds of people have died since rebels rose up in 2004 demanding political autonomy and a greater share of profits from the region's natural oil, gas and mineral resources.