The strike was called by Greece's two largest unions to protest against proposed legislation to reform the country's pension system, as well as new tax collection measures and the privatization of companies such as Olympic Airlines.
Some 2.5 million workers, including dockers, post office employees and national railway workers have come out on strike. Many schools and hospitals were shut down. Journalists have also joined the strike, meaning that information on events in the country is scarce. Transport services were also severely disrupted.
Two protest rallies are also planned for the Greek capital of Athens on Tuesday.
"Millions of Greeks are striking today and we expect them to march to parliament later in the day," a spokesman for the private sector umbrella union (GSEE) said.
The Greek parliament is expected to hold debates on the proposals next week.
