The country of 2.4 million people has faced multiple crises since Russia's 2022 invasion of neighbouring Ukraine that have tested the pro-EU government, which sees membership of the 27-member bloc as critical to breaking free from Russia's orbit.
Recent polls suggest the ruling pro-EU Party of Action and Solidarity (PAS) could struggle to keep its majority and would need to seek a coalition with others in the 101-seat legislature.
Opposition forces such as the pro-Russian Patriotic Bloc and the nominally EU-friendly Alternative alliance are courting voters bothered by high prices, slow reforms and scepticism over closer ties with western European countries.
The Patriotic Bloc says it wants friendship with Russia, "permanent neutrality" and a "state that serves the people, not officials".
The Kremlin denies meddling in Moldova's affairs and says the country's government is stoking anti-Russian sentiment for political purposes.
Any coalition would likely complicate President Maia Sandu's push for Moldova to join the EU by 2030, which would require extensive legislative work.
A 2024 referendum on EU membership only just cleared a 50 per cent majority.
"If we have a coalition, you can forget swift European integration given the options for ... partners," said a former senior official, speaking anonymously to give a frank assessment.
The European Union has vocally backed Sandu and considers a friendly Moldova, which applied for EU membership in 2022 alongside Ukraine, key to snuffing out Russian influence on its eastern flank.
In August, the leaders of France, Germany and Poland visited Chisinau to underline their support for the government's EU bid.
Moldova has a Romanian-speaking majority and a large Russian-speaking minority, and political power has alternated for decades between Russia-aligned and EU-aligned groups.
Russian troops are stationed in a separatist region, Transnistria, that broke from Moldova's control in a brief war in the early 1990s.
Sandu has described the vote as Moldova's most consequential election ever.
Addressing the country on Monday, she said Russia was spending hundreds of millions of euros to sway the vote and recruiting hundreds of people to stir disorder.
"Today, with utmost seriousness, I tell you: our sovereignty, independence, territorial integrity and European future are in danger," she said.
Moldovan police have stepped up searches in recent weeks into illegal party financing.
On Monday, security forces arrested 74 people in sweeping raids over alleged Russian-backed efforts to stoke unrest.
Patriotic Bloc co-leader Igor Dodon, a former president, said some members of his alliance were targeted.
"The criminal PAS regime is trying to intimidate us, frighten the people and silence us," Dodon said.
Election officials on Friday barred the Heart of Moldova party, part of the Patriotic Bloc, from taking part in the election following a court ruling limiting the party's activity for one year.
Moldova's justice ministry requested the restrictions following searches on Heart of Moldova party members that led to allegations of voter bribery, illegal party financing and money laundering.
The electoral commission said all 36 candidates proposed by Heart of Moldova will be removed from the bloc's list of candidates, and gave the bloc 24 hours to adjust its list to meet the representation thresholds required by electoral law.
Last month, fugitive tycoon Ilan Shor, sanctioned by the United States and EU as an alleged Russian agent, openly offered Moldovans monthly payments of $US3000 ($A4500) to join anti-government protests.
Voters will head into the election after years of economic malaise - largely from the war in Ukraine and an energy crunch sparked by Russian cuts to critical gas supplies.
Inflation hovers at about seven per cent and many voters are bitter.
"People don't see, in their daily lives, the benefits of EU accession," said Anastasia Pociumban of the German Council on Foreign Relations.
Meanwhile, corruption remains persistent and reforms in key areas like the justice system have moved slowly.
