The theory of current collection of a moving cylindrical probe is investigated. Volt‐ampere relations are derived for two distinct cases: (i) The general‐ion current for accelerating collector potential and its special cases, including general‐ion current to the stationary probe, orbital‐motion‐limited current to the moving and the stationary probes, and sheath‐area‐limited current to the moving and the stationary probes; (ii) the general‐electron current for the retarding collector potential and its special cases, including general‐electron current to the stationary probe and random‐electron current to the moving and the stationary probes. Orientation of the cylinder with respect to the drift velocity vector is taken into account. Volt‐ampere characteristics are included for illustrating the functional behavior of the current relations.