In this thesis, we present an LTE model atmosphere analyses of a group of early B-type postasymptotic giant branch (pAGB) stars. With initial masses::; 9Mo, post-AGB stars form an important group of evolved stars and provide a unique opportunity to study stellar evolution almost on a human time-scale. Post-AGB stars have spectral types ranging from K to Band luminosities between 103 and 104Lo. These objects ended their asymptotic giant branch (AGB) evolution phase with a peliod of strong mass loss (10-7 - 1O-4Moyr-l ) and have been evolving from cooler to hotter temperatures at almost constant luminosity on a timescale of ~ 104yr. B-type pAGB stars span a wide range in effective temperature (10 000 - 30000K). Their expected surface gravities (log g) and effective temperatures (Terr ) coincide with those of B stars evolving from the main sequence. Therefore systematic observational analyses are required to to distinguish these two groups. Furthermore, post-AGB stars may be divided into four distinct groups bqsed on their chemical composition. In this thesis, groups I and II represent post-AGB stars which are very metal deficient with CjO~l and metal poor with CjO