To provide a method for efficiently synthesizing and purifying a 5- substituted indole derivative useful as a raw material for intermediates for medicines and agrochemicals.

This method for producing the 5-substituted indole derivative (formula III) (wherein R2 and R3 denote each independently hydrogen atom or an alkyl group; and R4 denotes amino group or nitro group) is characterized as comprising reacting an indoline derivative (formula I) (wherein R1 denotes a protecting group having a structure of C=O or S=O; and R2 and R3 have each same definition as described above) with a reagent having a nitrating ability under conditions in which protonation of the N atom in the indoline derivative can be suppressed, regioselectively providing a 5-nitroindoline derivative (formula II) (wherein R1, R2 and R3 have each same definition as described above) and then carrying out dehydrogenation and deprotection.