The proportion fell from 64% in 2006 but was still significantly higher than for many other tumour types such as colorectal cancer (24%), cervical cancer (10%) and female breast cancer (4%)
Among patients with all types of cancer, 20% were diagnosed through A&E.
Patients whose cancer diagnosis is made via A&E are less likely to survive and more likely to experience long-term health problems than those whose disease is picked up at an earlier stage through a GP referral.
Sarah Mee, head of policy at The Brain Tumour Charity, said: “The figures for brain tumour patients are moving in the right direction but there is a long way to go.
“That's why we are funding new research into delays affecting adult brain tumour diagnoses and what can be done to tackle the problem.
"We want to build on the success of our HeadSmart campaign to raise awareness of brain tumour symptoms in children, which has already reduced the average diagnosis time for children with brain tumours from more than nine weeks to less than seven weeks."