Background: The long-term management of chronic disease requires the adoption of complex dietary recommendations, which can be facilitated by regular coaching to support behavioral changes. Telehealth interventions can overcome patient-centered barriers to accessing face-to-face programs and provide feasible delivery methods, accessible regardless of geographic location. Objective: This systematic review assessed the effectiveness of telehealth dietary interventions at facilitating dietary change in chronic disease. Design: A structured systematic search was conducted for all randomized controlled trials evaluating multifactorial dietary interventions in adults with chronic disease that provided diet education in an intervention longer than 4 wk. Meta-analyses that used the random-effects model were performed on diet quality, dietary adherence, fruit and vegetables, sodium intake, energy, and dietary fat intake. Results: A total of 25 studies were included, involving 7384 participants. The telehealth dietary intervention was effective at improving diet quality [standardized mean difference (SMD): 0.22 (95% CI: 0.09, 0.34), P = 0.0007], fruit and vegetable intake [mean difference (MD) 1.04 servings/d (95% CI: 0.46, 1.62 servings/d), P = 0.0004], and dietary sodium intake [SMD: 20.39 (20.58, 20.20), P = 0.0001]. Single nutrients (total fat and energy consumption) were not improved by telehealth intervention; however, after a telehealth intervention, important clinical outcomes were improved, such as systolic blood pressure [MD: 22.97 mm Hg (95% CI: 25.72, 20.22 mm Hg), P = 0.05], total cholesterol [MD: 20.08 mmol/L (95% CI: 20.16, 20.00 mmol/L), P = 0.04], triglycerides [MD: 20.10 mmol/L (95% CI: 20.19, 20.01 mmol/L), P = 0.04], weight [MD: 20.80 kg (95% CI: 21.61, 0 kg), P = 0.05], and waist circumference [MD: 22.08 cm (95% CI: 23.97, 20.20 cm), P = 0.03]. Conclusions: Telehealth-delivered dietary interventions targeting whole foods and/or dietary patterns can improve diet quality, fruit and vegetable intake, and dietary sodium intake. When applicable, they should be incorporated into health care services for people with chronic conditions. This review was registered at http://www.crd.york.ac.uk/PROSPERO/ as CRD42015026398.