Almost a third of Londoners overall but nearly two-thirds of Muslims suffered substantial stress following the 7 July bombings in the city, researchers say.
A number 30 bus was blown up in Tavistock Square
Muslims may have suffered more because of fears of reprisals, they said.
The British Medical Journal study also found that 32% of the 1,010 questioned were to reduce use of public transport.
But researchers said the study - carried out before the 21 July attacks - showed the bombers had not created a city too stressed to get on with life.
The research was carried out by London's Kings and University Colleges and the Health Protection Agency.
Fifty-two passengers were killed when four suicide bombers attacked three Tube trains and a bus on July 7.
The interviews for the study took place from Monday 18 to Wednesday 20 July - before the failed bombings on London's transport network on 21 July.
Nearly one in three (31%) of participants reported having suffered substantial stress, and 32% reported they would reduce the amount they used the Tube, trains, buses, or go into central London.
Some 46% of those surveyed said they did not feel safe travelling by Tube, and 33% did not feel safe in central London.
People who had difficulty contacting others by mobile phone on the day of the attacks were more likely to have suffered from stress, as were those who feared a loved one may have been injured or killed.
Overall, people with a strong religious conviction were more likely to report feelings of stress.
Being white and having previous experience of atrocities - such as IRA bomb attacks in London - was associated with reduced stress.
Only 12 participants (1%) felt that they needed professional help to deal with their emotions, whereas 71% had spoken to friends or relatives.
The researchers said this suggested that most people were able to rely on lay support networks.
Researcher Dr Neil Greenberg said: "It is quite a good thing that people should try to make sense of what happened by talking it through with those who understand them the best.
"Our findings show that we are resilient, and suggest that if the aim of the bombers was to create a city full of people so stressed that they could not get on their lives then they certainly failed."
Dr Greenberg said Muslims might have been more vulnerable to stress because of concern about the consequences of the bombings, such as possible reprisals from those who blamed the Islamic community in general.
Dr Monica Thompson, from the Trauma Stress Clinic, in London, agreed that most people seemed to have coped well with the bombings.
But she said people who were either directly caught up in the attacks, or witnessed the results first hand were much more likely to suffer from stress.
Dr Thompson's clinic has so far received 26 referrals of patients exhibiting signs of post-traumatic stress disorder.
Symptoms of this condition do not usually become apparent for a least a month.