The superstar is crazy about the late British royal's ''gangsta'' fashion sense and loves all the structured pieces the princess wore in the 80s.
Listing the celebrities on her best-dressed list, she enthused: ''Nicole Richie. She just pisses me off, she's so good. But you know who is the best who ever did it? Princess Diana. She was gangsta with her clothes. She had these crazy hats. She got oversized jackets. I loved everything she wore.''
The Bajan singer's passion for clothes began as a child when she would watch her mother experimenting with daring looks, and she aspired to be as stylish as her when she grew up.
Rihanna said: ''My love for fashion - let me say, my admiration for fashion - started with my mum. I used to watch her get dressed. She was around my age now, and she was so fly. I remember not even knowing how to do that because I was such a tomboy.''
The 'Pour It Up' hitmaker has several fragrances to her name as well as a clothing line for high street store River Island and she says the ventures are close to heart.
She explained: ''I'm a bit of a workaholic. I'm afraid of opportunities passing me by. I love being creative and have these different outlets now. But these are things that I actually care about.
''My mum was a make-up artist and she sold perfume. I knew all the fragrances as a kid and I would know them by heart just by the smell.''
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