Many students spend a lot of time and energy looking for the reflected image in telescope but failed in the experiment of the adjustment and use (the measurement of the prism apex angle by autocollimation method)of spectrometer，because of the high difficult of adjustment of spectrometer．These difficulties can be ascribed to the original complicated steps and high requirement of handler．We improve the adjustment steps of the spectrometer，separate the steps of the adjustment telescope focusing at infinity and the direction of the optical axis of the telescope．We only use the circular horizontal instrument in the process of adjusting the optical axis of the telescope，omit the process of using a double-plane reflector，greatly reduce the adjustment steps，which make the whole adjustment process more simple and more operable．