1H,4H-3,6-dinitropyrazolo［4,3-C］pyrazole (DNPP) was synthesized from acetylacetone via monocyclization, diazotization， bicyclization, nitration, oxidation, and decarboxylative nitration. The overall yield of DNPP was 11.3% and 4% higher than that reported before. The synthesis of 4-amino-3,5-dimethylpyrazole was carried out by one-pot method which shows a number of advantages in comparison with the procedure adapted in the literature, including eliminating the use of mixture acid and iron power, shorting the reaction time (from 72 h to 24 h), improving the yield (from 79.1% to 92.0%), and simplifying the post-treatment. In addition, both nitration and decarboxylative nitration were studied.