People who had taken aspirin even once the previous year were much less likely to develop cancer of the middle or lower parts of the stomach, according to a study based on 311,000 people in the US.
There was also a 32 percent reduction for the same type of stomach cancer in people who used other types of non-steroidal anti-inflammatory drugs (NSAIDs).
However, aspirin does not protect against oesophageal cancer or cardia-gastric cancer at the top of the stomach, which results of previous studies had suggested.
Taking aspirin regularly has been found to cut the risk of bowel cancer, but it is not currently recommended because side effects could include bleeding within the abdomen.
Now, scientists believe that placebo controlled trials, which would assess risks and benefits should be conducted to see if NSAIDs can be used to protect against stomach and oesophageal cancers.
Study author Christian Abnet, based at the National Cancer Institute in America (NCIA), said: 'We found that the risk of non-cardia stomach cancer was lower in people who had taken aspirin, and this risk lowered the more regularly they took it.'
'Interestingly, our results didn't show a significant cut in the risk of oesophageal or cardia stomach cancer, so it's important that we continue to review data that suggests otherwise,' he added.
'The number of people who survive at least five years following a diagnosis of stomach or oesophageal cancer is low, so it's important to increase our understanding of ways to prevent the disease and to investigate aspirin as a possible preventive drug,' said Abnet, according to an NCIA release.
Each year, around 8,000 people are diagnosed with stomach cancer in Britain; nearly 5,250 people die of the disease.
These results were published in the British Journal of Cancer.