Point defect concentrations in InGaAsP grown from liquid phases were calculated. Vacancies and antisites were taken to be dominant defects. The calculated antisite concentrations decrease with increasing band gap, while the vacancy concentrations are weakly dependent on composition. Although development of dislocations is known to be easier in InGaAsP lattice matched to GaAs than in those lattice matched to InP, the difference in the vacancy concentration between them is small when their growth temperatures are assumed to be the same. However, a high growth temperature usually adopted for InGaAsP on GaAs will result in larger vacancy concentrations.