* PM Babis likely to win second attempt at confidence
* Forms minority government with Social Democrats
* Backing of Communist to give it majority, draws protest
* Babis was clear election winner, struggled to get majority (Updates with Babis quote, more)
PRAGUE, July 11 (Reuters) - The Czech parliament is expected to give its backing on Wednesday to a new, centre-left minority cabinet led by billionaire Andrej Babis, ending his nine-month struggle to secure a parliamentary majority.
The new government, combining Babis's ANO party and the Social Democrats, will rely for support on the Communist Party, giving it a political say for the first time since the fall of Communism in former Czechoslovakia in 1989.
Most parties have rejected working with Babis, whose ANO won an election last October, because he faces fraud charges related to a 2 million euro European Union subsidy a decade ago. He denies any wrongdoing.
Together, ANO and the centre-left Social Democrats hold 93 seats in the 200-seat lower house of parliament, with the pro-Russian, anti-NATO Communists agreeing to lend another 15 votes under a deal that has been criticised by opposition parties.
"I want to ... stress that this is a very serious moment, the return of the Communist party to power and influence in the Czech Republic," Petr Fiala, leader of centre-right main opposition party, the Civic Democrats, said in parliament.
The confidence vote, mandatory for any new cabinet, is expected sometime later on Wednesday.
Speaking before the debate, Babis said his government would focus on investment and maintaining sound public finances, which have been in surplus in recent years amid a period of strong growth and a labour market with the EU's lowest unemployment.
He also aimed to give the country a stronger voice in the EU and continue to push the bloc to strengthen security to get migration under control.
"We will continue to be active, and make effective alliances (in this)," Babis said.
Babis's appeal stems from his image as someone who can dislodge the mainstream parties, seen by many voters as ridden with corruption. His rise to the top of Czech politics has mirrored progress made by populist movements across a number of EU countries.
Opponents, however, accuse him of eroding democracy due to the vast empire he built in chemicals, farming and also media. He has transferred the group to a trust fund to comply with conflict of interest laws.
Babis has repeatedly said he would keep the Czech Republic on a pro-Western course and avoid the kind of sparring over checks and balances that has landed neighbouring Poland and Hungary in conflict with Brussels.
But he backs central European peers in rejecting EU-prescribed quotas for member states to accept asylum seekers fleeing war in the Middle East and northern Africa. His hard line reflects public mood in a country where six in 10 refuse to accept any war refugees, according to surveys, and nearly all the rest would provide only temporary asylum.
The Communist Party leadership agreed to back the new administration even though Babis, who has been caretaker prime minister since a first attempt to win confidence for a one-party cabinet failed in January, refused some of their demands.
One was for cutbacks in the Czech contribution to NATO military missions abroad. Another sought representation on the supervisory board of the biggest state-controlled company, electricity producer CEZ.
The Communists are allied with pro-Russian President Milos Zeman, and their role in supporting the cabinet will give the president more political leverage. (Reporting by Jan Lopatka and Jason Hovet Editing by Catherine Evans)