We demonstrate an on-chip microring laser on Y b 3 + -doped thin film lithium niobate (Yb:TFLN) fabricated by photolithography-assisted chemo-mechanical etching technology. Multiwavelength laser emissions around 1025 nm from the microring resonator pumped by a 980 nm laser diode are observed with the lasing threshold of 10 mW. Experimentally, up to 14 longitudinal modes are obtained from the fabricated Yb:TFLN microring laser, and this on-chip microring laser is a promising light source for multiple wavelength channels in optical communications and biosensors.