The effects of treatment by ultrasound (US), inoculation of Pediococcus acidilactici BP2 strain (BP), and their combination (US-BP) on the quality characteristics of beef jerky were investigated during fermentation for 6 days. Moisture contents and water activity were highest after the US and US-BP treatments (P < 0.05). These effects were attributed to the decreased moisture mobility in beef jerky during ultrasonication. Meanwhile, samples treated with US and US-BP displayed more broken muscle fibers and larger gaps and cavities between the adjacent muscle bundles, resulting in lower shear force values compared to the other samples (P < 0.05), which indicated that the US and US-BP treatments improved the tenderness of beef jerky. Moreover, treatment with BP promoted the flavor development of beef jerky. The US-BP treatment improved the sensory attributes of beef jerky. In conclusion, US-BP is a promising strategy to improve the quality of beef jerky.