Six weeks after the reinstatement of David Begelman as Columbia Pictures studio chief, there is a mounting backlash in Hollywood to the move, according to studio sources, particularly in the wake of a growing barrage of press coverage.

Heads of other studios are said to be incensed that Begelman's return to power after admitting that he forged checks and embezzled more than $61,000 from the company has focused attention on what critics allege to be a wide range of financial irregularities involving movie companies.

"The hostility level to Begelman is rising to a pressure point," said one studio executive who declined to be identified. "Everybody's feeling the heat, and most people are concerned that things will get worse the longer Begelman stays on the job. Everyone seems to be thinking that everyone in Hollywood is a crook - which is not true. But the Begelman thing is tainting Hollywood with a very broad brush."

Lew Wasserman, chairman of MCA Corp., which owns Universal Studios, and who is considered one of Hollywood's elder statemen, is said by friends to be "outraged" by Begelman's return to a position of responsibility after an investigation revealed he had forged checks issued in the name of actor Cliff Robertson, director Martin Ritt and others.

In an interview, Wasserman only would say that "Columbia probably could have handled it better than they did," indicating it should have made full disclosure about what was involved in Begelman's defalcations when it reinstated him. "If they had a problem, they should have put it out in the open," Wasserman said.

The MCA chief, however, also was angry at a spate of charges that have surfaced in press accounts that kickbacks, short-changing of profit participants and other forms of cheating are common studio practices. "I think to condemn all of Hollywood for Columbia's problems is a cheap shot," Wasserman added.

When Begelman was returned to his post on Dec. 19 after a two-and-a-half month suspension, Columbia said he had "emotional problem which prompted these acts," but said he was undergoing psychiatric care so that "his continuing effectiveness as an executive" would not be impaired. In the only interview he has given since the affair blew up, Begelman said his acts were "aberrational" and represented "neurotic displays of self-destructiveness."

The pressure to oust Begelman has increased this week with the appearance of an article in the current issues of New West and New York magazines which casts doubt about how "aberrational" Begelman's embezzlements were.

The article alleges that when Begelman was the agent for singer Judy Garland in the early 1960s (along with producer Freddie Fields), he wrote numerous personal checks totaling more than $100,000 against her production company's account.

The allegations are made by Sid Luft, a former husband of Judy Garland, who said he is reactivating a decade-old suit against Begelman.

One charge is that Begelman wrote 13 checks totaling $35,714 to "cash" on Garland's Kingsrow Enterprises account in 1962 and proceeded to cash them at the Hotel Sahara and the Dunes Hotel in Las Vegas.

The article also says that although Begelman always has told friends that he attended Yale University and is listed as a Yale graduate in Who's Who, he never attended that school.

Stephen A. Kezerian, director of Yale's news bureau, confirmed that fact. "We've run through the records and all the files, and there's never been a Begelman on the alumni records of Yale - this includes the entire university," Kezerian said.

Attempts to reach either Begelman or his attorney were unsuccessful, and they did not return phone messages requesting a response.

Jean Vagnini, a spokeswoman for Columbia, said that everything at the company was business as usual and that she did not know of any outside pressure on the company to reverse its position on Begelman.

One Columbia executive, however, confirmed that the studio has been feeling pressure over it handling of Begelman incident, and that "the impact of all of these revelations is cumulative."

In Hollywood, there was a growing feeling that Begelman's days might be numbered.

"It's not right for a major studio to be headed by a guy who does things like that," said one Hollywood attorney. "It just isn't good for the industry. It's also 'bet David' time. And when there are 17 sleuthsdigging, they're going to get him."

Meanwhile, there is also growing discontent with the posture of actor Robertson who has been charging that the lact of prosecution of Begelman represents a law enforcement "cover-up," but who has been unwilling to come forward as a complainant, even though he has offered to testify.

Robertson first discovered Begelman's embesslement when he received a government tax form from Columbia in early 1977 for $10,000 even though he had not worked for the studio in the previous year except to do some gratis promotional stops. Chasing down what happened finally led Robertson to a discovery that Begelman apparently had cashed a check for $10,000 with a forged endorsement. Robertson reported matter to the local police, but nothing happened, and the eventually went to the FBI with his story.

The police indicated first that a jurisdictional squabble had held up the investigation, and later explained that Columbia's unwillingness to complain about Begelman's acts made it futile to proceed.

But in response to the cover-up charges, Los Angeles District Attorney John Van deKamp several weeks ago ordered his office to conduct a criminal investigation, and the DV's investigators were supposed to interview Robertson by telephone yesterday. He has maintained his posture that the police can proceed because they have all of the facts, and no complaint on his part is necessary.

A source in the DA's office said that they still were awaiting a final report where Columbia studios is located. he said that in any criminal case, a complainant is not absolutely necessary because it is the people of the state who are the victims and, when no one is pressing a complaint, the police department has authority to act on its own. However, he indicated that any prosecution might be easier if Robertson would take the further step of actually complaining as a victim of forgery.