The immature stem of asparagus is the edible part.Normally, the stem of tetraploid plants is thicker than that of diploid plants, so the germinating seeds and seedling shoot tips of JinGang701 asparagus (Asparagus officinalis L.) which is the main cultivar in China was used as test material, and the colchicine solution was used to induce tetraploid.The result shows the following:(1)germinating seeds dipping method: The highest frequency of variation and pure tetraploid were 20% and 83.33% while the bourgeoning seeds were dipped in 0.2% colchicine concentration and shaken at a speed of 100r/min for 6 h;(2) Seedling injection method: The frequency of variation and pure tetrapioid were 14% and 43.75% when the colchicine concentration was 0.20% and the injection time was 4 d, and this was the best result;(3)The method of germinating seeds dipping method is better than seedling injection method.