When can you let puppies leave the mom dog?

Can they - yes, but puppies should stay with mom and the litter until 8 weeks of age. Usually as they start on solid foods, mom comes around less and less but it is important to allow them the full 8 weeks or longer to be together. This is a critical learning stage for the puppies to develop dog social skills that will aid them later in life. It is a proven fact that puppies taken earlier have a higher percentage of developing behaviorial issues as they grow up.