The possibility of direct detection of light fermionic dark matter in neutrino detectors is explored from a model-independent standpoint. We consider all operators of dimension six or lower which can contribute to the interaction $bar{f} p to e^+ n$, where $f$ is a dark Majorana or Dirac fermion. Constraints on these operators are then obtained from the $f$ lifetime and its decays which produce visible $gamma$ rays or electrons. We find one operator which would allow $bar{f} p to e^+ n$ at interesting rates in neutrino detectors, as long as $m_f lesssim m_{pi}$. The existing constraints on light dark matter from relic density arguments, supernova cooling rates, and big-bang nucleosynthesis are then reviewed. We calculate the cross-section for $bar{f} p to e^+ n$ in neutrino detectors implied by this operator, and find that Super-K can probe the new physics scale $Lambda$ for this interaction up to ${cal O}(100 {TeV})$
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