Barcelona star Dembele limped out of Saturday’s 2-1 win over Getafe with a thigh injury.
The £97million summer arrival from Borussia Dortmund was brought in as a replacement for the departed Neymar.
But Barca boss Valverde now faces a selection headache with the 20-year-old expected to be sidelined for four months.
There is concern Barca’s three-pronged forward attack, which also includes Lionel Messi and Luis Suarez, may have to be reformed in the wake of Dembele’s injury.
But Valverde insists the team’s set-up can remain the same without the France international.
“We have various players, (Gerard) Deulofeu, Aleix Vidal, Denis (Suarez), Andre (Gomes),” the boss said.
“We will look for alternatives to play in the first XI.
“We will also take Barca B into account.”
Dembele will fly to Helsinki tomorrow to consult a specialist about his injury.
He is expected to be ruled out until the New Year.
Dembele was replaced by Deulofeu, who only re-joined Barca from Everton in the summer for £10.5m.
Gomes, meanwhile, is free to leave the club in January, while both Denis Suarez and Vidal were on the market.
Barcelona B currently sit ninth the Spain’s second tier, with Argentine forward Anthony Lozano having netted twice for the club.
Dembele came off after feeling his leg during the match with Getafe and his last act was a back-heel in the far corner of the pitch – something that may have further aggravated his injury.
“He’s a player who has never had a muscular problem, he has no experience of recognising when you have a small niggle,” Valverde added.
“To do a back-heel is the worst, the most aggressive, thing you can do to the hamstring.
“It’s not normal but it can happen. A more experienced player maybe would have let the ball go out.”
Barcelona face 13th-placed Eibar in La Liga tomorrow and Valverde is expecting a close encounter.
“It’s a different game to what we’ve had up until now,” he said.
“They will try to press us up high up. They’re a team who steal possession a lot on opposing grounds and who read the second ball very well.”