The invention discloses a hollow cylindrical collector diagnosing ionization chamber, and aims to solve the problems of small collection area and insufficient sensitivity of the ionization chamber in the prior art, further improve the performance of the ionization chamber, increase the measurement accuracy, increase the collection area, and lower the influence of combination loss on measurement. According to a technical scheme, the hollow cylindrical collector diagnosing ionization chamber comprises an ionization chamber shell, a collector, an insulator and an ionization chamber base, and is characterized in that the collector is arranged inside the ionization chamber shell; the lower part of the ionization chamber shell is provided with the ionization chamber base; the collector is arranged on the ionization chamber base through the insulator; an enclosed ionization chamber cavity is formed among the ionization chamber shell, the collector and the ionization chamber base; the collector is of a hollow structure; the collection area is increased through the hollow structure.