In order to achieve the fast and non-destructive detection of mini watermelon quality during growth process, the basic information collection methods for fruit measuring were analyzed quantitatively. The PLS modeling results showed that both the tissue water content and soluble solids content could obtain good results at the top position and the equator. The modeling performance had some differences with basic chemical information at different depths, but both the tissue water content and soluble solids content could got the best results in the middle information area which was under 2~3cm from the rind. The correlation coefficients of tissue water content at the top location and the equator were 0.953 and 0.924, and the RMSEP were 0.510 and 0.766, respectively. The correlation coefficients of soluble solid content at the top location and the equator were 0.952 and 0.929, and the RMSEP were 0.666 and 0.732, respectively. For the mini Jingxiu watermelon, the best foundation information area for NIR detection was the middle area.