Police and ambulance crews were called to the scene - at the junction with Portobello Road - at 10.05am.
Officers have since confirmed that a 40-year-old man died at the scene.
The force is also asking for anyone who may have witnessed the collision, or has dashcam footage, to get in touch with them as soon as possible.
Sergeant John Easton, of Edinburgh’s Road Policing Unit, said: “We’ve now contacted the cyclist’s family and our thoughts are with them at this very difficult time.
“Extensive road closures and diversions were put in place in the Portobello area to allow emergency services safe access to the scene, and I want to thank motorists and the local community for their co-operation.
“I’d urge anyone who may have witnessed this or who has information that could be relevant, especially those travelling in the area at the time with dashcam footage, to contact us as soon as possible if they have not already spoken to officers.”
Sir Harry Lauder Road was closed in both directions, between Portobello High Street and Fishwives Causeway, with a diversion put in place eastbound on Seafield Road until around 2pm.
Portobello High Street remained closed between Portobello Road and Bath Street until 3.30pm while collision investigations continued and the lorry was recovered.
Those with information can call Police Scotland on 101, quoting incident number 1001 of 13th March 2019.
Sign up to our newsletter: enter your email in the box at the top of this article to get daily updates straight to your inbox.