Based on the social capital theory and upper echelons theory, we proposed the hypothesis model about TMT internal social capital, TMT behavioral integrity and strategic decision making speed. Then, the data obtained via questionnaire from 67 TM’s by software SPSS19.0 & AMOS17.0 are analyzed, then the theoretical hypotheses as mentioned above are verified. Results show that: Different dimensions of TMT internal social capital have significant positive impact on TMT behavioral integrity, TMT behavioral integrity has significant positive impact on strategic decision making speed, and TMT behavioral integrity as an intermediary variable played a brokering role in the relationship between TMT internal social capital and strategic decision making speed.