A House Judiciary subcommittee began its final drafting sessions yesterday on a major revision of immigration laws with a decision to penalize citizens who hire undocumented aliens to do housework or baby-sitting.

The bill already provided penalties for employers of four or more people who hire illegal aliens.

Rep. John W. Bryant (D-Tex.), who sponsored the amendment, argued that it should also apply to people "in the highest economic brackets who hire domestic help."

The penalties range from a civil fine of $1,000 to $2,000 on the first violation for each alien involved to criminal penalties of six months in jail and $1,000 fines for repeat offenders.

Besides the penalties for employers, the bill provides an amnesty program for undocumented aliens who have lived in the United States since Jan. 1, 1982, and $841 million in increased enforcement funding for the Immigration and Naturalization Service during the next two years.

The Immigration subcommittee turned down an amendment by Rep. Charles E.Schumer (D-N.Y.) to expand the legalization program to every illegal alien in the country since Jan. 1, 1985.

In another change, the subcommittee approved an amendment by Rep. Daniel E. Lungren (R-Calif.) to deny welfare, food stamps, Medicaid and unemployment benefits to illegal aliens.

The subcommittee is expected to decide today to get around one controversial issue by setting up a separate bill to deal with how many foreign workers should be allowed into the United States for brief periods to pick perishable crops.

Hearings are expected to be held on the guest-worker issue early next year.

Subcommittee action on the immigration bill is expected to be completed today.

The immigration bill then will be sent to the full committee. Final House action on the measure is expected next year.

The Senate has passed a similar bill.