Purpose/Objective(s): To assess response rate, duration of response, and overall survival after low dose involved-field (IF) radiation therapy (RT) in patients with recurrent low grade lymphoma or chronic lymphocytic leukemia (CLL). Materials/Methods: Between June 2001 and May 2008, 43 consecutive patients with indolent lymphoma or CLL were irradiated with a palliative intent with a total RT dose of 2x2 Gy using 6-18 MV photons. Median age was 73 years (range, 39-88), and there were 24 women and 19 men. The diagnosis consisted of low grade follicular lymphoma in 17 patients (40%), CLL in 13 (30%), and other types of low grade lymphoma in 13 (30%). IFRT was given either following (n = 32; 75%) or before (n = 11; 25%) chemotherapy. Systemic treatment consisted of median 6 cycles of chemotherapy (n = 32; range, 2-19 cycles) and/or median 4 cycles of rituximab (n = 29; range, 3-16 cycles). Median time from diagnosis was 48 months (range, 1-249 months). Median follow-up period following IFRT was 20 months. Results: Overall response rate was 86%. Thirteen patients (30%) had complete response (CR), 17 (40%) partial response (PR), 7 (16%) stable disease (SD), and 6 (14%) progressive disease (PD). Median overall survival for patients with a positive response (CR/PR/SD) was 41 months, and 6 months for patients with PD (p = 0.001). Median time to in-field progression (TTP) was 21 months, and median time to out-field progression was 8 months. Three-year in-field control rate was 92% in CR patients (median was not reached). Median in-field TTP was 9 months in PR, and 6 months in SD patients (p < 0.05). There was no statistically significant difference in terms of in-field TTP according to lymphoma type but there was a trend towards worse response for patients with follicular grade 3 lymphoma. In univariate (logrank test) and multivariate (Cox model) analyses, younger age (< 70 years), positive response to RT, and no previous chemotherapy were the best factors influencing the outcome. Conclusions: Low-dose IFRT is an effective, simple, and long-lasting palliative treatment in the management of patients with recurrent low grade lymphoma or CLL.