Human Rights Watch said governments in the Middle East should follow Syria's example.
"Syria has stepped forward to protect a particularly vulnerable group of refugees," said Bill Frelick, refugee policy director for the organisation, on Friday.
The Syrian government allowed 244 Palestinian refugees to enter the country on Tuesday after they had been stranded on the border between Iraq and Jordan.
Jordan, fearful of a large influx from among the 34,000 Palestinian refugees estimated to be living in Iraq, had refused to allow the Palestinians to enter.
The Palestinians said the killings of fellow community members in Baghdad had forced them to flee.
Under Saddam Hussein, Palestinians living in Iraq were perceived by some to be a privileged community, receiving free housing and government jobs.
"These Palestinians are refugees twice over. Israel denies them their right to return to their homeland, but Iraq has become a country where they are targeted for violence," said Sarah Leah Whitson, director of the group's Middle East and North Africa division.
"Syria's action in admitting them should be an example for other countries in the region," she added.
Human Rights Watch said Syria had also allowed 40 refugees to move direct to Syria from Baghdad.
Syria hosts 425,000 Palestinian refugees and about 500,000 Iraqis who have fled sanctions, war and persecution.