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Abstract. A portable specialized visible and near-infrared (Vis/NIR) detective instrument for evaluation of grape quality was designed in this study to satisfy the need of fast, nondestructive detection in grape industry. The hardware components and software modules were introduced in this paper work. The holographic concave diffractive grating combined with charge-coupled component was chosen as core part to obtain spectra date of grape samples in this system, and halogen light source combined with optical fiber were chosen to provide stable Vis/NIR light source. In order to adapt diverse varieties of grapes with different sample sizes, an adjustable sample cuvette with internal and external threads was designed. The software which can easily perform model updating was written by C# based on windows operating system. The CIE L*a*b*, total solid soluble contents (SSC) and total phenolic compounds (TP) of two varieties from Vitis vinifera L. were taken into calibration and prediction using least squares support vector machine (LS-SVM). Seventy samples of each variety were used as external samples to exam the performances of device and established models. The results showed that the a* values, SSC and TP could be well predicted with RMSEP of 3.15, 1.39 % and 0.24 g/kg for ‘Manicure Finger‘; and 0.78, 1.56 % and 0.22 g/kg for ‘Ugni Blanc‘, respectively. This study provides a feasibility of portable specialized Vis/NIR detective instrument for grape quality and a reference method for other specialized instrument.