The police crackdown on Thursday followed a stern warning to citizens to stay away from further demonstrations called by an opposition group.
"Around 100 people tried to demonstrate on Andalus Street on Thursday afternoon, but security forces confronted them, arresting about 50, while the rest dispersed," a witness said.
The protest was called by the London-based Movement for Islamic Reform that called for nationwide demonstrations on Thursday against the arrest of dissidents.
Despite being foiled, the attempted protest in Jiddah was significant.
It came a little over a week after the kingdom witnessed a rare demonstration in Riyadh, during which hundreds of protesters clashed with police.
Earlier, Saudi Interior Minister Prince Nayif bin Abd al-Aziz Al Saud said demonstrations were illegal and urged people to stay away from them.
"Protests violate existing rules and anyone who takes part in them will be subjected to deterrent punishment meted out by the Islamic court," the minister said.
Interior ministry officials also said that 83 people, including three women arrested during last week's Riyadh demonstration, were still in custody and would appear in court.
"Authorities arrested 271 people, of whom 188 were freed after proving that they had been drawn into the crowd and acted out of curiosity," a ministry spokesman said.
"Protests violate existing rules and anyone who takes part in them will be subjected to deterrent punishment meted out by the Islamic court"
Prince Nayif bin Abd al-Aziz Al Saud
Saudi Interior Minister
The London-based opposition group had called for more demonstrations in Riyadh and other parts of the kingdom on Thursday.
Saudi Arabia's Higher Judiciary Council has also cautioned the people from joining the protests.
Shaikh Salih bin Muhammad al-Lihaidan, the head of the Council, in remarks made to a daily newspaper, said the demonstrations were "demagogic" and authorities were duty-bound to "stand up firmly" to such activities.
"Calls for demonstrations and sit-ins amount to calls for strife and to an attempt to spread vice and undermine security," he said.
The undersecretary of the Ministry of Islamic Affairs and Religious Endowments, Shaikh Abd al-Aziz bin Abd Allah al-Ammar, alleged that the calls for protests were made by people "seeking to incite strife."