"Achalov has replaced Colonel Alexei Pavlushko in this capacity," Igor Konashenkov said.
Gen. Achalov is a former commander of the 62nd Russian military base in Akhalkalaki, recently handed over by Moscow to Georgia as part of the complete withdrawal of Russian bases from Georgian territory.
Abkhazia declared independence from Georgia following a bloody conflict that left hundreds dead in 1991-1992, and peacekeepers have been stationed in the region ever since.
There have been frequent and mutual accusations of ceasefire violations from both Abkhazia and Georgia, whose President Mikheil Saakashvili has vowed to regain control of the region.
Peace talks broke off when Tbilisi sent troops into Kodori Gorge in July last year and established an alternative Abkhaz administration there.