  Strong optical and near-infrared (NIR) flares were discovered in the
afterglow of GRB 080129. Their temporal behaviors, the sudden emergence and the
quick disappearance, are rather similar to that of many X-ray flares (for
instance, the giant flare of GRB 050502B). We argue that the optical/NIR flares
following GRB 080129 are a low energy analogy of the X-ray flares and the most
likely interpretation is the "late internal shock model". In this model, both
the very sharp decline and the very small ratio between the duration and the
occurrence time of the optical/NIR flares in GRB 080129 can be naturally
interpreted. The initial Lorentz factor of the flare outflow is found to be
$\sim 30$, consistent with the constraint $\leq 120$ set by the forward shock
afterglow modeling. Other possibilities, like the reverse shock emission or the
radiation from the continued but weaker and weaker collision between the
initial GRB outflow material, are disfavored.
