The Senate Democratic Caucus agreed unanimously yesterday that former Vice President Hubert H. Humphrey, now a senator from Minnesota, should receive special title and special pay and allowances as a mark of respect for his former high office. If the Senate as a whole approves, the same benefits would go to any other former President or Vice President who subsequently becomes a member of the Senate.

The proposed benefits include: the title and role of "deputy president pro tempore of the Senate." The president of the Senate when the Vice President is away, and now a new position of deputy president pro tempore would be created.

Humphrey would also receive a chauffered limousine for his use the same as other high Senate offices, a salary equal to that of the majority leader ($52,000 instead of the normal salary of $44,600), the right to sit on the Democratic policy Committee, special office space in the Capitol, and a special staff equal to that given to the Senate Democratic assistant leader - two professional employees and two clerical.

The Democratic Caucus recommended these benefits as a mark of respect for Humphrey and future presidents and vice presidents who later join the Senate on the recommendation of a three-member unit consisting of Henry M. Jackson (D-Wash,), Abraham A. Ribicoff (D-Conn.), and Edward M. Kennedy (D-Mass.). The subcommittee was appointed by newly elected Senate Majority Leader Robert C. Byrd (D-W. Va.) Tuesday after Humphrey withdrew from the leadership race.

The perquisites are designed as a show of respect for Humphrey, who has recently had cancer surgery. Humphrey was Vice President from 1965 to 1969. Under the proposal, Humphrey would be included in leadership groups which periodically go to the White House for meetings with the President.

The package of benefits for Humphrey was, in effect, a substitute for a proposal previously advanced by Edmund S. Muskie (D-Maine) to make Humphrey chairman of the Democratic Caucus, a post normally reserved for the majority leader. Such a position would have carried more substantive power for Humphrey than the titles and benefits given him yesterday. The caucus put that proposal aside Tuesday when Byrd announced that he was creating the study unit to determine what special mark of recognition Humphrey should receiveas the party's grand old man.