To provide theoretical and technical basis for the application of preparations of bamboo vinegar and copper sulfate in the prevention of green algae in floating system for tobacco seeding, the soaking and spraying methods were employed to study the effect of different concentrations of preparations of bamboo vinegar and copper sulfate on green algae and tobacco seedling growth. The results showed that the preparations of bamboo vinegar and copper sulfate of different concentrations played a strong role in inhibiting green algae growth and had better effect than copper sulfate. Spraying 1:200 preparations of bamboo vinegar and copper sulfate could significantly promote tobacco seedling growth, and the leaf fresh weight increased by 15.80% compared with CK, with significant difference; spraying 1:50 preparations was not conducive to tobacco seedling growth. It was recommended to spray 1:200 preparations of bamboo vinegar and copper sulfate in floating system for tobacco seeding, which could promote tobacco seedling growth and reduce green algae to varying degrees.