In this paper, a $1550\mathrm{nm}$ all fiber monostatic laser range finder system based on linear chirp modulation and heterodyne detection is presented. The fiber end face signal is used as a range starting indicator. The transmitted laser power is $5\mathrm{mW}$ with a laser pulse length of $131\mathrm{\mu s}$ and a linear chirp bandwidth of $40\mathrm{MHz}$ . The telescope with an aperture of $3\mathrm{cm}$ couples the return light into a single mode fiber. Better than $14\mathrm{cm}$ distance accuracy and $26\mathrm{dB}$ SNR can be achieved for a wood target at a distance of about $43\mathrm{m}$ by using the above system setup. Several experiments with different system parameters are conducted. The system performance is tested under variable laser pulse length, linear chirp bandwidth, local oscillator power, and background noise. Finally, an application of the linear chirp modulation heterodyne laser range finder in a spaceborne ranging system is proposed.