The 36-year-old Klose — appearing in his fourth World Cup finals — slid in at the far post to equalise in the 71st minute.
The classic poacher’s strike earned Germany a 2-2 draw — and put Klose in the history books alongside Ronaldo.
Ronaldo, 37, was quick to offer his congratulations, having scored his 15th World Cup goal at Germany 2006 before retiring.
“Welcome to the club,” he wrote on his Twitter account in German and English.
Klose had sat out Germany’s 4-0 thumping of Portugal on Monday when Thomas Mueller claimed a hat-trick in his place, but the veteran came off the bench to spare Germany’s blushes.
“You really want to come in when the team is winning,” admitted Klose.
“If a team like Ghana gathers momentum, it is of course difficult.
“It was much warmer than the Portugal game, and it was very intense.
“It doesn’t matter whether I play from the start or come off the bench: all games are important and 15 goals in 20 World Cup games isn’t bad.”
Klose claimed a goal record even before flying to Brazil when he became Germany’s all-time top scorer and his goal against Ghana extended his tally to 70 goals in 133 internationals.
He bettered the previous record set by Gerd Mueller, who scored the winner in the 1974 World Cup final to claim his 68th goal in 62 appearances for West Germany.
Klose was the top-scorer at the 2006 World Cup in Germany with five goals, having finished second with another five at the 2002 tournament, while he scored four in South Africa four years ago.
His longevity — he has been a constant presence since making his debut in 2001 — is remarkable and saw him celebrate his 36th birthday the day the Germans arrived at their World Cup base.
“I’m incredibly pleased for him, that is another high point in his unparalleled career,” Germany coach Joachim Loew said Saturday after Klose’s latest milestone.
“It has not been an easy season for him, but he has done it again and got himself in top shape for a tournament.
“For a coach it is of course great to have options like him on the bench.”
Klose has said next year will be his last in the famous white shirt of Germany, but he could yet break Lothar Matthaeus’ record of 150 caps for his country.
He signed a contract extension in May with his Italian side Lazio until June 2015, with an extra year’s option, but expects next season to be his last.
“At the moment, I assume that 2015 will be the end, but it depends on my fitness and any injuries,” he told German daily Bild.
Klose flew to Brazil with question marks over his fitness after an injury-ravaged season restricted him to seven goals in 22 appearances for Lazio.
But the veteran hot-shot delivered the goods when they mattered for Germany, just as he has done so often in the past.
“When he’s fit, then he is terribly important for my team,” said Loew.
“His secret is his professionalism, his strength is his will.”