There is a well-established link between cancer and venous thromboembolism (VTE), and patients receiving chemotherapy for esophageal or gastric cancer appear at high risk of developing VTE. The incidence of VTE in the neoadjuvant setting in these patients is poorly understood, as is the role for thromboprophylaxis during neoadjuvant chemotherapy. A PubMed search was conducted using a combination of terms including; esophageal & gastric cancer, deep venous thrombosis (DVT), VTE, neoadjuvant, chemotherapy and chemoradiotherapy. One hundred and fifty-four articles were retrieved and a narrative review was conducted. For patients with esophageal and gastric cancer the incidence of VTE ranged from 4 to 19%. Gastric cancer (Odds Ratio [OR] 6.38, [95% CI: 1.96- 20.80]) and Stage III/IV disease, (OR 5.16 [95% CI: 1.29-20.73]) were identified as risk factors for developing VTE. Neoadjuvant chemotherapy was identified as an independent risk factor for developing VTE. Symptomatic and asymptomatic VTE have a similar effect on mortality. Median overall survival for asymptomatic VTE was 13.9 months (95% CI: 5.0-∞) versus 12.8 months (95% CI: 4.7-30.3) if the VTE was symptomatic. Neoadjuvant chemotherapy is a significant risk factor for VTE in patients with esophageal and gastric cancer. Intervention to minimize the risk using pharmacological and mechanical thromboprophylaxis should be considered, and this should start in the neoadjuvant period.