Refusals are frequently performed in our daily lives.Based on the speech act theory of Austin and Searle,with the theoretical frame of the politeness theory put forward by Brown and Levinson,It presents a comparative study of speech acts of refusal in Chinese and American English.The results show that refusals vary in directness with situations and cultures;On the one hand,both languages employ the three directness types,namely the direct refusal speech act,ability of negation and indirect refusal speech act,and prefer indirect refusals.The situational variability of directness in both languages follows a similar trend.On the other hand,Americans are more direct than Chinese.Furthermore,Chinese shows the lower degree of situational variation in the use of the three directness types.People’ s choices of refusal strategies are influenced by social power and social distance.From all these evidence,we maintain that the cross-linguistic differences are due to basic differences in cultural values. Refusals are frequently performed in our daily lives.Based on the speech act theory of Austin and Searle, with the theoretical frame of the politeness theory put forward by Brown and Levinson, It presents a comparative study of speech acts of refusal in Chinese and American English The results show that refusals vary in directness with situations and cultures; On the one hand, both languages ​​employ the three directness types, of the direct refusal speech act, ability of negation and indirect refusal speech act, and prefer indirect refusals. Situational variability of directness in both languages ​​follows a similar trend.On the other hand, Americans are more direct than Chinese.Furthermore, Chinese shows the lower degree of situational variation in the use of the three directness types. People’s choices of refusal strategies are influenced by social power and social distance.From all these evidence, we maintain that the cross-linguistic differences are due to basic differences in cultural v alues.