This paper sketches out the effective Hamiltonian and basis set adopted in the spectroscopic calculation of asymmetric top free radicals, and details the machine implementation of the spectral analysis of asymmetric top free radicals, the design and usage of the program package. To demonstrate the application of this program, analyses have been performed on the far infrared laser magnetic resonance spectrum of (NO2)-N-14-O-16(I = 1) and the infrared diode laser ...