It is getting so you can't get a government job unless you already have a government job.

If you doubt it, check with anybody in the army of people who have been trying, without success, to earn the title, pay and benefits of civil servant.

Although it has a way to go before it can be considered a closed shop things are getting much tougher for the 11 million people who try each year - with varying degrees of vigor but mostly without success - to get on the federal payroll.

Many job applicants in Washington where government is the primary industry - are finding that job advertisements from federal agencies are meaningless because the applicants don't have "status." Status, in this case, is civil service status and it means that an individual has either worked for Uncle Sam before or has been cleared by the government and granted status which is a legal and very necessary job-hunting license.

Many top federal officials, including the chairman of the Civil Service Commission and President Carter (both, in a sense, temporary political appointees) are worried about the increasingly in-bred nature of government. But there is little that can be done about it until outside economic conditions change, the government expands, or merit system rules are altered substantially.

Most people coming into regular federal jobs get there by being rated eligible - through a test or rating process - and being put on a register.

In fiscal year 1974, the government hired 231,410 people from that register. The next year the incoming figure dropped to 194,557 and in fiscal year 1976 it was down to 153,371.All signs indicate that there will be less "fresh blood" from the outside coming into government during this fiscal year or next, unless things change.

There are a lot of reasons why fewer outsiders are getting into government these days. In the first place, more outsiders are trying to work for Uncle Sam. They want in because of the security the government offers, because of increasing federal pay scales and favorable retirement benefits.

These things all look better in a shaky economy when auto companies are firing workers, television manufacturers transfer operations abroad and firms are put out of business or curtail operations because of the high price of fuel and raw materials.

At the same time more people are trying to get into government, the government itself is offering fewer jobs. Federal employment - despite all those scare stories to the contrary - has been declining slightly in recent years, and is way down from the big Vietnam war buildup of 1967 through 1969.

Turnover in government also is down at a time when there are fewer jobs in government to be had and there are more people outside trying to get in.

Federal officials say that normal retirement levels have dropped in recent years, because many federal workers who would normally retire and take jobs in industry have decided to stay put.

Since government pensions are based on length of service, and on the highest 3'year average salary, many workers are staying longer to benefit from annual pay raises that increase their eventual retirement income.

Because federal agencies can pick and choose in this job market - and because of merit-system requirements - many agencies now will not consider an applicant unless he or she has "status" or re-employment rights. Getting status takes time, and most agencies simply don't want to - or need to - wait for an outsider to qualify and get on the register, a process that can take months.

In addition, the government has its own promote-from-within programs - both by law and by union agreement. These merit-system programs, combined with upward mobility training programs for minorities mean that fewer new people are coming in.

"We hope the figures will improve over the next few years," a Civil Service Commission job expert said, "because we don't want to become a closed shop. Obviously anytime you have 150,000 outsiders' coming in each year you don't have a closed shop.

"But the data is there. It is getting harder for people outside the government to get jobs, and it probably will remain like that until government expands, retirements get back to normal or the administration does something to change the selection and hiring system."