In recent years, a number of studies about firm size and innovation find that small firms introduce more innovations than their larger counterparts. This has been widely interpreted as indicating that small firms are more innovative than large ones, or that small firms are more efficient innovators than large ones. In China, however, the relationship between innovation and firm size in high tech firms still remains undiscovered, so this paper is completed to serve this purpose. We hope that the conclusions we made in this paper can test those accepted viewpoints，and especially that some interesting conclusions can be found to explain the special situations in Chinese high—tech firms．In study．survey data from 960 high tech firms are used to analnyze the relationship between the firm size and innovation capability．According to the generally used classification standard by firm’s employees．the paper also analyses the distribution pattern of innovation expenditure．R＆D expenditure．sale scale and innovation ratio of different firm size Ievels．After comparing our analyzing results with foreign scholars and general industrial firms，we find three special trends as follows．Firstly，R＆D intensity decreases with the increasing of employes’number．Secondly innovation intensity generally presents a convex U distribution trend．Finally，innovation efficiency of considerably small high—tech firms is low．