Objective：This study aims to prepare 68Ga-DOTA-K-PEG2-（K-FA）2（68Ga-DOTA-2P-FA2）and investigate the value of 68Ga-DOTA-2P-FA2 for targeted imaging of ovarian cancer and peritoneal metastasis. Methods：Characteristics of 68Ga-DOTA-2P-FA2 was investigated in vitro after its preparation. A nude mouse model of subcutaneous human ovarian cancer（SKOV3）and its peritoneal metastasis was established to investigate the biodistribution of 68Ga-DOTA-2P-FA2 in vivo. The receptor blocking group，the negative control group of human lung cancer（A549）and blank control group were set up. The microPET imaging was performed at 120 min（in mice bearing subcutaneous tumor xenograft）and microPET-CT imaging was performed at 60 min（in mice bearing peritoneal metastases）after tail vein administration. Results：68Ga-DOTA-2P-FA2 was stable in vitro with radiochemical purity of （96.30±1.28）%. Folate receptor affinity（IC50）was 17.1 nmol/L. Octanol/water partition coefficient（lg P）was -1.89. Radioactivity uptake of subcutaneous ovarian cancer reached a peak at 120 min after tail vein injection，which could be effectively blocked by overdose free folic acid. It could be removed rapidly in blood，heart and lung，generating a low uptake in liver，and mainly excreted through kidney. Pre-injection of pemetrexed could effectively accelerate the excretion of radioactivity in kidney. MicroPET imaging showed radioactivity uptake of subcutaneous ovarian cancer was significantly higher than that of folate receptor blocking group and that of the negative control group. The radioactivity uptake of peritoneal metastases was significantly higher than that of blank control detected by microPET-CT. Conclusion：68Ga-DOTA-2P-FA2，which accumulated in tumor sites with high expression of folate receptor，was a good imaging agent for ovarian cancer and peritoneal metastases.