The company said it put a well in the Lublewo research area in to a test phase to determine its potential to produce natural gas following a successful hydraulic fracturing program.
Kamlesh Parmar, the company's chief executive, said the well is a milestone for the exploration program in Poland.
"The operations to bring the well into test production have gone very smoothly and we are delighted to see the well has flowed [natural gas] from the beginning," he said in a statement.
The European Investment Bank in June loaned Poland $132 million for the expansion of a pipeline that could bring gas, including domestically sourced liquefied natural gas, to the border of the Czech Republic, Slovakia and Ukraine.
The EIB said the Polish gas project is "crucial" to European energy security.
Poland is thought to be rich in shale natural gas reserves. In April, state energy company PGNiG said it would asses shale reserves with the Polish subsidiary of Chevron, though shale developments in the country have been slow to evolve.