The 32-year-old Pole's promising F1 career was cut short when he suffered serious injuries in a rallying accident
in February 2011 that required a partial amputation of his right forearm.
The legacy of that injury meant his arm movement was restricted and a return to F1, the pinnacle of motorsport, seemed unlikely -- until now.
Kubica completed 115 laps at Spain's Circuit de la Comunitat Valenciana Ricardo Tormo on Tuesday in a 2012 spec Renault-powered E20 car.
The 2008 Canadian Grand Prix champion
admitted to "mixed feelings" following the test.
"For me, it has been an important day from an emotional point of view," Kubica said in a statement.
"It has been a long time away from the paddock and I have been through difficult periods, I kept working hard and a few years ago I felt it was impossible.
"I have mixed feelings, I am proud with what I achieved today, but also it shows what I have lost. I don't know what the future will bring, but I know one thing, after working for more than one year to prepare for this, I ran with good pace and consistent in difficult conditions.
"It is not easy after six years, but I knew I could do the job and I can be satisfied."
Renault F1 team sporting director Alan Permane praised Kubica's efforts after such a long time away.
"It is a tricky thing to jump into an F1 car after six years and it was a great performance from him," Permane said in a statement.
News of Kubica's test was warmly received by the F1 racing community.
Two-time world champion Fernando Alonso tweeted his approval while former Red Bull Racing driver Mark Webber said hearing about Kubica's test was the "Best news I've heard all week."
Kubica raced 76 times in F1 during five seasons initially with the Sauber team before switching to Renault in 2010.
His one and only victory came in Canada in 2008 and he finished on the podium 12 times before his F1 career came to an abrupt halt.