GaAs microwave monolithic integrated circuits (MMICs) with Ba1−XSrXTiO3(BST) capacitors have been developed. Spin-coating of sol-gel solution was used to make the BST thin film. The obtained BST film has a dielectric constant of 300 that is 50 times higher than the conventional SiN one. The capacitance has the frequency roll-off over 2 GHz, which is sufficient enough for a variety of consumer applications. The implemented GaAs MMICs with on-chip BST capacitors enable the positive-bias supply and high gain performance as well as the small package outline.