Mr Baynham died after being attacked in Trafalgar Square
A vigil for victims of hate crime is taking place in central London's Trafalgar Square.
Homophobic attack victims Ian Baynham, who died earlier this month, and James Parkes, who was injured in Liverpool on Sunday, will be among those honoured.
Speeches will be made before the two-minutes silence at 2100 GMT.
Organiser Mark Healey said: "If we forget about these victims we could become complacent and fail to learn from the past."
Mr Baynham, 62, from Beckenham, south-east London, died from brain damage two weeks after being attacked in Trafalgar Square on 25 September.
On Sunday night trainee police officer Mr Parkes, 22, was attacked by up to 20 people outside a gay bar in Liverpool's Stanley Street. He remains in hospital with multiple skull fractures.
Last week Metropolitan Police figures showed that 1,192 homophobic offences were reported in London in the year to September, up from 1,008 the previous year - a rise of 18.3%.
Mr Healey said: "This started off as a vigil for Ian but it soon became clear that it was also important to remember other victims of homophobic attacks and other hate crimes."
He added: "Whenever someone is attacked, pain and suffering is not just caused to them, but also to their family and the wider community.
"We hope the vigil will also inspire young people to tackle issues of equality in the community."
National and international equality groups have been encouraged to hold their own vigils to coincide with the London event, which has received the backing of Stuart Milk, the nephew of late US gay rights activist Harvey Milk.