The delivery came four days after the eastern European country declared a one-month state of emergency to secure gas supplies amid a crisis over rising prices.
Moldova has received its "first" delivery of non-Russian gas as the country grapples with a severe energy crisis.
The delivery of one million cubic metres of natural gas was supplied by Poland's PGNiG.
Chisinau said the "sample purchase" from Poland is meant "to test the ability to import gas from alternative sources and balance the low pressure in the natural gas supply system".
It added that the offer from PGNiG was one of seven the state company Energocom received after issuing a tender.
The delivery came four days after Moldova declared a one-month state of emergency to secure gas supplies amid a crisis over rising prices.
A spokesperson for the Ministry of Foreign Affairs told Euronews that "a similar contract for the same quantity and via the same mechanism was signed with the Dutch company Vitol".
"In order to ensure that the Republic of Moldova keeps the gas pressure at an acceptable level and to ensure the energy security of the country, Energocom bought gas at the market price and at the lowest price offered during the bidding," they said.
It comes as the cost of gas soars elsewhere in Europe, amid a perfect storm of factors including increased demand after COVID lockdowns, existing stocks being reduced by longer winters and weather conditions meaning renewables are not able to fill the shortfall.
Almost all of Moldova's gas imports come from Russia via Moldovagaz, a company formed with the Russian giant Gazprom.
A gas interconnector between Moldova and neighbouring Romania became operational in 2015 but currently only supplies the 35,000 inhabitants of Ungheni, a border town.
Only 67% of Moldova's gas needs are currently covered and negotiations with Gazprom are ongoing for deliveries beyond October 31.
But the government has warned it has "no confidence" in getting a positive outcome from the talks.
Critics have accused Gazprom and the Kremlin of hiking gas prices to punish Moldova after the 2020 election of pro-European President Maia Sandu.
Negotiations are also complicated as Moldovan gas must pass through the pro-Russian territory of Transdniestria.
The Financial Times newspaper also reported late on Wednesday that Gazprom is pressuring Moldova to delay energy sector reforms and a free trade deal with the European Union in exchange for cheaper gas prices.
Gazprom, meanwhile, accuses Chisinau of late payments and threatens to cut supply if a new contract is not signed.
In an emailed statement, a spokesperson for Gazprom said it "is negotiating with a counterparty to extend the contract to supply gas to Moldova exclusively on commercial terms."
"We do not consider it correct to comment on Moldova's agreements with other suppliers," they added.
Moldova's Foreign Ministry said that the government "is still in the process of negotiating with Gazprom about a long-term contract for the supply of natural gas to the Republic of Moldova."
"Negotiations are ongoing and we cannot comment about them at this stage," it also said, adding that "the authorities can end the state of emergency earlier as soon as the country secures a steady flow of gas."
According to the International Energy Agency (IEA), the country of 2.6 million inhabitants is almost wholly dependent on fossil fuel and electricity imports with only 20% of its energy demand met domestically in 2018.
It also has no gas storage facilities, which leaves it particularly vulnerable to geopolitical and pricing shocks. Disputes between Moscow and Chisinau in 2006 and 2009 left tens of thousands of Moldovan citizens without gas for days in winter. The second instance, which lasted weeks, saw Moldova activate the EU's Civil Protection Mechanism, which provided capacity heaters and electrical generators.
The European Commission President Ursula von der Leyen said on Wednesday that the EU will also release €60 million to help Moldova manage the energy crisis.
"Tomorrow's EU-Moldova Association Council will further strengthen our cooperation," von der Leyen said following a meeting with Moldovan Prime Minister Natalia Gavrilita.
"The European Union has always been with the citizens of the Republic of Moldova — both in good times and in difficult times," Sandu said in an earlier statement.
"We are grateful for the support provided by the European Union in managing the gas supply crisis."