The new Â£59.5m distribution centre and regional offices are based at Capital Business Park in Wentloog.
Around 400 more jobs could be in the pipeline as the company plans to open new stores across south Wales.
Aldi is the UK's fifth largest supermarket with more than 700 stores and 29,000 employees.
A Â£4.5m Welsh Government grant helped support the new development.
Dan Oakenfull, managing director of new the hub, said: "South Wales and the south west of England continue to be areas of significant growth for us, and the new distribution centre will help support our immediate and future expansion across the regions."
Economy Secretary Ken Skates said the opening of the centre was a mark of confidence in the Welsh economy.
Supermarket chain Aldi has opened its new warehouse on the outskirts of Cardiff, creating 422 jobs.