Abstract: Insufficient dispersion in pulp and high consumption are the drawbacks of conventional collectors,if used.The optimum formulae for the preparation of emulsified and micro-emulsified collectors are determined by single-factor experiment and pseudo-ternary phase diagram,and fine coal flotation test is made using the collectors thus prepared.Test result indicates that: the micro-emulsified diesel is much finer in size（0.065 mm on average） and exhibits a higher stability for its uniform distribution and dispersion in pulp; and for flotation of the fine coal which is identical to the test sample in property,if the similar flotation performance is expected,the use of micro-emulsified diesel can lead to higher flotation rate and lower consumption of flotation reagents.