Provided is a series of new poly-fluorosubstituted pyrazolopyrimidine compounds or salts. The compounds are Bruton's tyrosine kinase (BTK) inhibitors. The compounds have better kinase inhibition selectivity and pharmokinetic properties. Also provided is a preparation method for the compounds. Also provided is a combination therapy including the compounds in combination with another targeted drug composition or another drug. The optimised combination therapy has a cooperative effect, inhibits the existence of a tumour better than a single targeted drug, and causes certain tumours to completely disappear. The optimised combination therapy treats drug resistance and cancer recurrence of a tumour better than a single targeted drug, and the treatment cycle is shorter. The present invention also relates to a combined compound and a pharmaceutical preparation wherein said combined compound acts as an active ingredient, said pharmaceutical preparation being safer at a lower dosage and having a cooperative effect efficacy. Also provided is a method of using the compounds and a preparation thereof to treat and inhibit an autoimmune disease or illness, a heterogeneous autoimmune disease or illness, an inflammatory disease, a cancer or an illness.