CoCrFeNi high-entropy alloy (HEA) was fabricated by mechanical alloying (MA) and vacuum hot pressing sintering (VHPS). The phase and microstructure of alloys were characterized by X-ray diffraction, scanning electron microscope, inductively coupled plasma-optical emission spectrometer, and optical microscope. The mechanical properties and corrosion resistance were investigated by universal tensile machine, Vickers hardness tester, and electrochemical workstation. Results show that CoCrFeNi HEA prepared by MA-VHPS exhibits excellent ultimate tensile strength and elongation, compared with those prepared by the arc-melting method and the combined method of the electrochemical reduction (FFC) with VHPS. The hardness of CoCrFeNi HEA prepared by MA-VHPS is twice larger than that prepared by arc-melting. The CoCrFeNi HEA prepared by MA-VHPS displays corrosion resistance in 0.5 mol/L H₂SO₄, 1 mol/L KOH, and 3.5wt% NaCl solutions, comparable to that of the 304 stainless steel and CoCrFeNi HEAs prepared by FFC-VHPS or arc-melting.