The accurate determination of π‐bond energies, Dπ, in doubly‐bonded species has been an important issue in theoretical chemistry. The procedure using the divalent state stabilization energy defined by Walsh has been suggested, and the procedure seems to be conceptually reasonable and applicable to all kinds of doubly‐bonded species. Therefore, the aim of this study was to examine whether the procedure could be a reliable methodology for estimating the Dπ values for a variety of H2C=XHn species. To achieve a higher accuracy, the Dπ values were estimated at QCISD(T)/6‐311++G(3df,2p) level of theory combined with isogyric correction. The Dπ values estimated in this work were in excellent agreement with the extant literature values. On the other hand, in determining accurate Dπ values for doubly bonded species, especially in species with lone‐pair electrons such as H2C=O, it has been found that consideration of highly sophisticated electron correlation effects could be important. However, sufficiently accurate Dπ values have been obtainable at QCISD(T) or CCSD(T) levels with a 6‐311++G(3df,2p) basis set on geometries at relatively inferior correlated levels such as MP2 and B3LYP levels with a 6‐31+G(d) basis set. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2011