CHAZ BONO is enraged that his own mother has stolen the spotlight from him!

Just as the former “Dancing with the Stars” competitor reached his fighting weight and proudly began to display his new body, Cher grabbed headlines with a sexy lingerie photo shoot – vamp­ing as a slinky blonde bombshell on her new album cover.

“Chaz is furious,” an insider told The ENQUIRER.

“It seems Cher can’t let him en­joy his success without trying to do him one better. Chaz feels very con­fident in his new body. He literally worked his butt off to get there.

“Then here comes Mom, and with some blonde hair dye and a little computer magic, she’s flaunting how sensational she looks at 67.”

The “Believe” singer indeed looks half her age on the album ironically named “Closer to the Truth.” And when 44-year-old Chaz saw the pictures, he exploded.

“You’re such a fake!” he bellowed at Cher, according to the insider.

The transgender activist is espe­cially upset because he achieved his results the old-fashioned way through low-carb diet­ing, grueling gym workouts, cardiovascular dance classes and hours of martial arts prac­tice.

As The ENQUIRER reported earlier this year, Chaz has indeed become the incredible shrinking man, a weight-loss effort that began when he appeared on the syndicated TV show “The Doctors.”

In an inspiring display of willpower, the 5-foot-5 1/2 author and actor plummeted from an all-time high of 250 pounds last November to around 180.

Chaz recently turned heads as he showed off his new body on Sept. 3 in Los Angeles, arriving at an acting workshop in a tight T-shirt and shorts.

“Chaz looks great,” marveled an observer. “He has been losing weight steadily and now seems totally comfortable in his new body.

“He’s at the gym for several hours almost every day, and every time I run into him, there’s a little less to see.”

Added the insider: “Chaz says people look at him and they see a real person who suffered and struggled to drop weight and get in shape and isn’t afraid to be who he really is.

“When he looks at the new pics of Cher, he sees someone who is hiding behind the Hollywood glamor machine.”

Meanwhile, Chaz is getting a good ribbing from pals over his mom’s efforts to make time stand still – and it’s getting on his nerves.

But Cher responds to his complaints “by putting him down with a ‘what do you know’ attitude,” said the insider. “Chaz told her she has never been able to accept him as a man, and now she can’t stand it when people tell her he’s a good-looking guy.

“There should be a parade for Chaz celebrat­ing all he’s accomplished. Instead, everyone is talking about his half-naked mom.”