Ben Wood, Labour candidate in this month's by-election, says 307 businesses across Wem, Whitchurch, Ellesmere, Oswestry and Market Drayton are under threat.
Mr Wood called for an immediate cut in business rates, and said they should eventually be replaced with a new form of business taxation.
He said official Government data showed that 332,000 businesses were at risk across the country, employing more than 800,000 people.
Mr Wood said: “I started my working life selling tiles at a local hardware shop. I know the importance of small and medium businesses, and how important they will be to the future of North Shropshire.
“Labour wants to scrap business rates and, as your local MP, I will campaign to carry out the biggest overhaul of business taxation in a generation.
"I want local businesses in North Shropshire’s to have all the support they can get, and as a local lad I will always put North Shropshire first.”
Labour has proposed freezing business rates until the next re-valuation, and then increasing the threshold for small business rates relief from the current threshold of £15,000 to £25,000.
Mr Wood said Labour would pay for easing this burden on businesses by raising the UK Digital Services Tax to 12 per cent next year, raising £2.1 billion which would be spent on cutting business rates for small businesses and the high street.
In the long term, Labour would fund the replacement for business rates by shifting the burden of business taxation away from the high street towards large online tech giants, he added.