Rachel Reeves said the move would not deliver new energy “any time soon” and would not reduce prices.
It comes amid reports Liz Truss, the Conservative leadership favourite, plans to approve a series of new drilling licences if she wins the keys to Downing Street.
The Scottish Government has already voiced opposition to the proposals.
Ms Reeves said there was “obviously a role for North Sea oil and gas in the transition towards net zero”.
However, she insisted the cheapest form of energy comes from wind and renewables.
She added: "I think that that is the faster and the cheaper way to boost our energy security and resilience and in the meantime create really good jobs here in Scotland, paying good wages, as well as delivering on our objectives of greater energy resilience, so we're less reliant on [Vladimir] Putin and other dictators.
"I think that renewables is the right way to invest in our resilience as a country."
She made the comments on a visit to Catapult, a leading innovation and research centre for offshore renewable energy, in Levenmouth, Fife.
Asked if she would support the issuing of new licenses for drilling in the North Sea, Ms Reeves said: "I don't think that is the right approach.
"It's not going to deliver new oil and gas any time soon to meet the need.
"It wouldn't reduce prices, because it would still just be sold on the international markets.
"And there is a cheaper alternative with quicker lead times that would actually directly reduce people's gas and electricity bills."
Ms Reeves pointed to Labour's plans to extend the windfall tax on energy company profits, with this money then used to "keep people's bills low this autumn and winter".
She added: "That is my priority. Liz Truss's priority seems to be protecting the big profits being made by oil and gas companies, and that is not the right priority for a country where more and more people are being pushed into fuel poverty."
Elsewhere, the shadow chancellor was asked about the Scottish Government’s opposition to new nuclear power stations.
She said nuclear power “plays a really important part in our energy mix”.
Ms Reeves said: “I do support more investment in nuclear because it is part of what is needed to boost our resilience and reduce our reliance on dictators like Vladimir Putin, because we will have investment in home-grown renewables and nuclear energy here in Britain.
"Look, those are choices for the Scottish Government. But as a UK Chancellor, I would ensure that we are investing in those things that boost our energy security and help British consumers, whether they are in Scotland or England, Wales or Northern Ireland, get access to gas and electricity at the lowest possible prices.”
Asked if she would seek to overrule the Scottish Government on the issue, she said it was a decision for Scottish ministers.
She added: “There are lots of opportunities in England that I would pursue as Chancellor, and in Wales as well, to ensure that we have got the right energy mix.”