Rovins Iranian demonstrators - both opponents and supporters of Shah Mohammad Reza Pahlavi - criss-crossed Washnngton with boisterous but largely orderly marches and rallies yesterday bringing their conflicting messages to the White House, Embassy Row and the Capitol.

In contrast with Tuesday's violent clashes, yesterday's demonstrations resulted in only a few scattered arrests and some apparently minor injuries. Police carried out stiffer security measures: opponents and supporters of the shah were kept widely separated and the demonstrators themselves appeared to exercise more restraint than they had Tuesday.

The most serious incident yesterday took place shortly before 7 p.m. in Lafayette Park where anti shah protesters clashed briefly with U.S. Park Police said the incident began after a sticks, stones and pails of garbage. Police said the incident began after photographer complaining that he was being harassed by protesters, called for help. Four demonstrators were reported injured in that incident. They were treated at George Washington University Hospital and released.

The thousands of anti-shah demonstrators here - who denounced the shah as the " fascist" head of a represive regime supported with U.S military aid - appeared to view their two days of dawn-to-dark protest as a widely publicized, political triumph.

"The world knows of the Iranian students and their movement now," said one anti-shah demonstrator. "Across the U.S., people know of the struggle.They see it on television last night, in Europe too, and most important, in Iran they see us and know we fight on."

"We learned last night that news of our protest efforts had reached home (Tehran), and the people were rejoicing," asserted another anti-shah protester, who identified himself as Ali Azad, a student in Florida. "When they saw the shah wipe his eyes from the tear gas, they thought we had gassed the shah."

The shah's supporters - as well as the shah himself - responded to the anti-shah protesters with sharp criticism yesterday.

Said Hossini, a spokesman for a group of demonstrators supporting the shah, said in an interview, "I feel we have been very effective because we have been open. We did not hide ourselves like the other people. They were like animals. They beat women and children."

In a television interview yesterday morning on NBC's "The Today Show," the shah said, "The question is that now you know what kind of people we have to deal with. I have been told so that they have sticks and were attacking, were aggressive."

Tuesday's violence left 96 demonstrators and 28 police officers injured. Four of the most severely injured remained hospitalized yesterday at George Washington University Medical Center, including one - a 66-year-old man with a fractured skull -listed in serious condition.

Before nightfall yesterday, eight demonstrators were reported arrested in scattered incidents on disorderly conduct charges or for possessing dangerous weapons - poles or clubs. Although more than 70 persons were reported to have been given medical treatment at a command post in Lafayette Park, only seven were reported to have been taken to George Washington University Hospital for treatment. None was hospitalized.

Yesterday offered a series of contrapuntal Iranian demonstrations.

In the morning, some 2,000 to 3,000 anti-shah protesters massed in Lafayette Park, across pennsylvania Avenue from the White House, marching in winding processions and chanting, "Shah is a U.S. puppet - down with the shah." It was the site where most of Tuesday's anti-shah rallying had taken place.

At the same time, a group of about 300 supporters of the shah gathered at 17th Street and Pennsylvania Avenue NW, chanting "Long live his majesty." A long cheer went up as the shah drove in a small motorcade to the White House at 10:25 a.m.

Even the rhythms of the demonstrators chants appeared to show subtle differences. The anti-shah demonstrators' chants seemdd to echo the acrimonious drone of similar slogans shouted during the Vietnam war and civil rights protest era. The pro-shah partisans' voices rang out in bouncier and more traditional rythms, often resembling football cheers.

At midday, the demonstrators' stage shifted to Embassy Row, as the shah had lunch with Vice President Mondale at Anerson House on Massachusetts Avenue.More than 600 of the shah's opponents rallied at Dupont Circle and marched afterward to the front of the mosque on Massachusetts Avenue at Waterside Drive. They had set off toward the Iranian Embassy - further west on Massachusetts Avenue - but police halted them at the mosque.

Meanwhile, a small group of the shah's supporters stood at the corner of Massachusetts Avenue and 22d Street NW, carrying banners and small Iranian and American flags.

In the afternoon, the main scene of the demonstrations moved to the Capitol area, as the shah had tea with some members of Congress.

Hundreds of pro-shah supporters - some of them carrying baseball bats and wearing motorcycle helmets - gathered on the east and west steps of the Capitol and on a lawn across Independence Avenue from the Rayburn House Office Building. Meanwhile, close to 200 anti-shah partisans took up posts in a small park across Constitution Avenue form the Capitol.

At various times, members of the two opposing demonstrations taunted and jeered one another.

Jack I. Heller, a Washington lawyer representing the Irania - American Friendship Society, said in an interview that the pro-shah demonstrators were carrying baseball bats yesterday as a precaution because of Tuesday's violence.

"The word went out last night that only able-bodied men should show up here today. Their women and children stayed behind at the hotels." Heller said. Nodding toward a group of the shah's supporters who were swinging their baseball bats in the mild autumn air, Heller added, "About 40 of them walked into Sears last night and bought those bats. The salesman was so stunned that he called the police."

In an attempt to avoid a recurrence of Tuesday's violence, police sought to make certain the pro-shah and anti-shah demonstrators would be separated by considerable distances throughout the day yesterday, both as they marched through the streets and while they rallied in parks and elsewhere. This effort appeared largely successful.

"There's been no trouble since the groups were separated," D.C. Police Chief Maurice J. Cullinane said in an interview.

Police also took other measures, including confiscating many of the sticks, poles and clubs wielded by both pro- and anti-shah demonstrators. Capt. Joseph E. Mazur, of the D.C. Police Department's special operations division, said yesterday's policy was to seize any pole that was not attached to a banner or a sign on the theory that it constituted a dangerous weapon. Police, however, also ripped some poles from demonstrators' placards and then confiscated the poles, prompting complaints from some of the anti-shah protesters.

Security was also extraordinarily tight near the Capitol yesterday as more than 500 armed, uniformed Capitol police wer augmented by D.C. police.

The demonstrations, on a warm, almost cloudless fall day, tied up traffic at various points in the city and caused other disruptions, including closing elevators yesterday afternoon in the Rayburn Building. A Park Service spokesman said damage caused by the demonstrations at Lafeyette Park and the Ellipse had been estimated at $20,700 - mainly for replacing sod and trees.

The demonstrators themselves apparently sought to exercise restraint yesterday after Tuesday's violent clashes. One technique employed by leaders of the anti-shah demonstratoions was to send groups away from Lafeyette Park for marches elsewhere in the city.

"We had trouble controlling people (Tuesday)," said a spokeswoman for th anti-shah protesters who identified herself only as Sheila. "We figured that if we keep the group in the park as small as possible, we might have better order than we did before. All of that walking and marching (was) making them tired.

Also contributing to this account of yesterday's demonstrations were Washington Post staff writers Donald P. Baker, B. D. Colen, John Feinstein, Paul Hodge, Alfred E. Lewis, Thomas Morgan, Timothy S. Robinson, Paul W. Valentine, Joseph D. Whitaker and Juan Williams.