We prepared carboxylic acid group terminated linear polybutylene adipate (PBA) by melt polycondensation of adipic acid with 1,4-butanediol in the presence of titanium(IV) isopropoxide (TIP) as a catalyst. High molecular weight branched PBAs were synthesized through the branching reaction between the carboxylic acid group terminated PEA and branching agent such as glycerol or pentaerythritol in the presence of TIP. The weight-average molecular weights of the branched PBAs were found to be in the range of about 100,000-240,000 by gel permeation chromatography. Mechanical properties of the linear and branched PBAs were measured on an Instron tensile tester. The moduli of the branched PBAs had lower values of 320-450 MPa than those of the linear PBAs, whereas the elongations at break of the branched PBAs were in the range of 530-590%, which are much greater than the linear PBAs.