The former Bake Off star revealed that her greatest fear is to be left alone if her husband Paul passed away.
Speaking to Good Housekeeping, the 82-year-old said: 'I shouldn't think about it, but I can't bear the thought of being a widow.
'Many of my friends are now widows and I'm so proud of them. It's a scary thing.'
Reflecting on her marriage, which has lasted more than half a century, Mary Berry said that while she's very happy, he's not the romantic type.
Mary Berry and her husband Paul
'It is a long time! I'm so lucky. We are very happily married. I appreciate him enormously and tell him so – which is not reciprocated! But there we are', she said.
'But I don't mind at all, because he is very old-fashioned. I think he is quite happy with his lot. Paul is not in the slightest romantic,' she said.
Spilling the beans on the secret behind their lasting marriage, Mary revealed that they still follow advice that her father gave to her husband.
'Some very good advice my father gave Paul is never to go to bed on an argument. Otherwise one of us – and it will be me – will be awake all night.
'Paul will have gone to sleep! It is much better to discuss a whole situation and see how you feel. I think that is very good advice,' the baker said.
Mary Berry and Paul tied the knot in 1966, at Charlcombe Church close to her parents' home in Bath.
Mary Berry on her wedding day
The pair went on to have three children - Thomas, Annabel and William, who died in a car accident aged 19 - and the mum only took five weeks off after each baby.
'None of my friends had careers, but I loved my work and Paul was marvellous with things like the school run', she said.
'It wasn't like today. There was no maternity leave and if you didn't come back to your job soon, someone else would jump into your shoes. By then, I was cooking editor of a magazine and there was lots of competition.'