A precoding scheme based on single-end channel estimation is proposed to mitigate crosstalk in received signals in intensity modulation direct detection (IM-DD) mode group division multiplexing transmission system based on photonic lantern. The scheme uses a signal feedback mechanism which is made up of a circulator and a splitter. Signals in receiving ends will return to the transmitting end for single-end channel estimation and the channel transmitting matrix will be used for precoding. The experimental results show that after the precoding processing in the back-to-back and 500-m few mode fiber mode group division multiplexing transmission systems, the transmitted power of LP₀₁--LP₀₁ and LP_11a--LP_11b channel signals can be reduced about 3 dB and 1 dB respectively when the bit error ratio (BER) is at the threshold of 1.3×10 ^-2 forward error correction (FEC). This paper provides an effective solution to reduce signal crosstalk in point-to-multipoint IM-DD mode group multiplexing transmission.