An extented molecular distance-edge (MDE,μ) vector of chain hydrocarbons including alkanes, alkens, alkynes, dienes, and alkenynes are defined and calculated. Quantitative structure property relationship (M1) on boiling point of chain hydrocarbons is proposed by multiple linear regression method with good results: root mean square error RMS=4.69K and correlation coefficient R=0.9976. Random sampling modeling and cross validation (CV) procedure are also performed and satisfactory results have been obtained with average correlation coefficient being R=0.9975, 0.9971 and average RMS=4.72K,4.83K respectively. In order to generalize MDE for other organic compounds ,a novel molecular distance edge (MDE) vector, which can be applied to discribe the molecular structure of both fatty aldehydes and fatty alkanones, is developed by using dying factors to express the carboxyl ( > CO) based on a molecular distance edge (MDE) vector of alkanes. and the QSPR model between the new MDE vector and boiling point (Tb) is also developed for 72 aldehyde and alkanone compounds with good results: R=0.9989 and RMS=3.93K.Random modeling procedure is also performed with average correlation coefficient being R=0.9990 and average root mean square error RMS=4.12K; and quantitative prediction is done with R=0.9980 and RMS=5.52K. All these results show that the MDE vector is a useful vector in QSPR/QSAR studies.