Multiple-input and multiple-output (MIMO) radar is a new radar system which is proposed in recent years. Taking advantages of waveform diversity, MIMO radar can improve the identifiability of the parameter and the adaptive technology for receiving data on radar, and enhance the parameter estimation and target detection performance. In this paper, several traditional nonparametric adaptive technologies are introduced in parameter estimation method. In the case of a known number of targets, a multi-target parameter estimation method that combines Capon, Generalized-Likelihood Ratio (GLR) and approximate maximum likelihood (AML) estimation is proposed, which is called CGAML. It can estimate the target position and the corresponding complex amplitude accurately. And then a target detection model is established under multi-pulse accumulation conditions of MIMO radar, which analyses the performance of MIMO radar on target detection. Compared with the conventional phased array radar, MIMO radar system shows better advantages.