HAVANA — A sudden jump in import taxes on Monday threatens to make life tougher for some of Cuba’s new entrepreneurs and will mean higher prices for many of their customers by raising the cost of goods ranging from jungle-print blouses to jewelry.

The new measures steeply hike duties on cargo shipments, as well as on many bulk goods brought in by airline passengers, a crucial supply line for many of the small businesses the government has been trying to encourage as it cuts a bloated workforce. Officials insist the taxes are similar to those in other countries, but many small-business owners view the change as an ominous sign.

While the published official description seems aimed at items such as clothing, soap, food, and other personal-use goods, it is so complex it leaves importers of other products unsure if they will be affected, now or in the future.

Some of the entrepreneurs, such as Javier Ernesto Matos, say they have prepared for the blow by stocking up on parts before the tax takes effect.

He also has prepared for a worst-case scenario if supply dries up entirely: “The strategy we have in mind is to consolidate in a single shop and leave prices the same to recoup what we can from our investment,’’ said Matos, who together with two business partners operates three mobile phone repair shops.

Others say they’ll have no choice but to raise prices. That, along with the higher taxes on goods brought in by friends, has worried consumers in a country where the average monthly wage is about $20.

‘‘For our family these are important items, from a little soap to a backpack for school,’’ a woman identified as Loraine wrote on the state-run Cubadebate website. ‘‘We all make sacrifices to help them. Nothing falls from the sky. Why are they turning their backs on reality? Knowing how many shortages there are in the country, why be so strict?’’

While President Raul Castro has tried to expand the private sector, the government has done little to provide wholesale outlets where businesses can buy parts and materials for the goods they sell, so many supplies are unavailable or prohibitively expensive due to high government retail markups.

Arturo Lopez-Levy, a Cuban-born economist at the University of Denver, said it’s not unusual for countries to levy high customs duties, but Cuba has exceptional circumstances that make it inadvisable right now.

‘‘The right timing was to create the wholesale market first and then try to crack down on this type of activity,’’ Lopez-Levy said. ‘‘If you don’t have a wholesale market, then you are implementing the measures without the proper sequence, especially if you really want to promote the small- and medium-size nonstate sector.’’

‘‘In the long term, this resolution was necessary,’’ he said. ‘‘Right now, it’s a mistake.’’

The new duties seem primarily targeted at so-called ‘‘mules,’’ who make frequent shopping trips to places such as Ecuador, Panama, and Miami and bring back duffel bags bulging with food, underwear, shoes, and electronics.

Starting Monday, Cubans who travel abroad more than once a year not only will pay higher tariffs, they’ll pay in hard currency rather than the more-easily obtainable national peso, which trades at 24 to the US dollar and is used for most salaries.