The move is the latest setback for Huawei, which saw the arrest of the daughter of the firm's founder in Canada and U.S. efforts to blacklist the company internationally over security concerns.
The detentions come amid the Chinese tech company coming under western scrutiny for being linked to China's government and having equipment which could contain "backdoors" for use by government spies.
Polish authorities have reportedly arrested Huawei's sales director and an ex-security agency staffer on allegations of spying.
If convicted, they could face up to 10 years in prison.
Huawei issued a statement from its Chinese headquarters saying it was aware of the situation in Poland and was looking into it. Here, people walk by Huawei's offices in Warsaw on Friday.
Geopolitical tensions over Huawei have intensified since Canada arrested a top executive last month at the request of United States authorities.
In addition to this, Huawei have come under fire from authorities in Norway, Germany, the U.S., the UK, Australia and New Zealand, with several countries outright banning the use of their devices or equipment used in 5G mobile networks.
Orange Polska spokesman Wojciech Jabczynski told AFP that "ABW officials carried out items belonging to one of our employees on Tuesday". USA officials have not produced much public evidence for these concerns, but this arrest will underscore Huawei's potentially malicious ambitions.
"A Pole and a Chinese citizen have been arrested on suspicion of spying".
The Chinese government said it was "highly concerned" over reports of the arrest of a Chinese businessman for alleged espionage.
Huawei said it "complies with all applicable laws and regulations in the countries where it operates, and we require every employee to abide by the laws and regulations in the countries where they are based". The US has accused Huawei of potentially building "back doors" into its communications equipment to allow penetration by Chinese intelligence, in a similar manner as Kaspersky allegedly did with its anti-virus software on behalf of Russian intelligence.
The European Commission is aware of the reports of the arrests and will reach out to the Polish authorities for further information, spokeswoman Maja Kocijancic told reporters in Brussels.
Even without concrete evidence, many countries around the world are banning Huawei from working on their national 5G grid, with many more considering the same move.