A multi channel receiver scheme with simple structure and low cost design was presented in this paper. A Ka band millimeter wave receiver with three channels was designed based on the scheme. The superheterodyne structure and secondary down conversion technology were used for the receiver. The signal from different channel can be received in the same channel by switching different firs local vibration. The spectrum planning was simulated and optimized by ADS software, and thus the appropriate local vibration and intermediate frequency can be chosen. A Ka band multichannel receiver with simple structure and excellent performance was developed. The main specifications of the receiver were as follows: 28.5 GHz±100 MHz, 27.5 GHz±100 MHz, 26.5 GHz±100 MHz, ripple in band of less than 3 dB, noise coefficient of less than 5, gain of 45 dB and controlled 30 dB gain.