Deformation of microbeams including microcantilever (MCL), simply supported microbeam (SSMB), clamped-simply supported microbeam (CSSMB), and clamped-clamped microbeam (CCMB) induced by evaporative microdrop is theoretically investigated. MCL will bend upwards while SSMB, CSSMB, and CCMB will bend downwards when there is a sessile microdrop on the top surface of the microbeam. The maximum deflection of MCL is proportional to the cube of the contact radius and sin theta, and the maximum deflections of SSMB, CSSMB, and CCMB are proportional to sin theta and nearly proportional to the cube of the contact radius. During constant contact angle (CCA) evaporation, as the contact radius reduces, the maximum deflection will decrease greatly. While during constant contact radius (CCR) evaporation, as the contact angle decrease, the maximum deflection will increase when the contact angle is larger than 90 degrees, while the maximum deflection will decrease when the contact angle is less than 90 degrees. Some numerical examples are given to show how MCL, SSMB, CSSMB, and CCMB are deformed by evaporative microdrop and the numerical simulations agree well with the theory.