One adverse impact by tourism in the Nepal Himalaya is deforestation resulting from the use of wood for fuel. The magnitude of this impact, however, has not yet been understood well. As a first step to gain such an understanding the number of visitors to Sagarmatha (Mount Everest) and Langtang National Parks was estimated for the period of 1990-94. Group and individual styles of trekking were distinguished because they exhibit different wood burning behavior, with individual trekkers consuming fuelwood at “hotels”. Overall, 7, 077 group trekkers and 4, 629 individual trekkers visited Sagarmatha NP. The respective totals for Langtang NP were 3, 397 and 4, 964. The 1990 and 1994 surveys indicate that there were 3.75 guides and porters per group trekker and only 0.23 guides and porters (including porterage by yaks) per individual trekker in Sagarmatha NP. The corresponding ratios for Langtang NP are estimated as 1:3.14 for group trekking and 1:0.32 for individual trekking. In Sagarmatha NP the number of guides and porters is divided almost equally between trekking agency staff from Kathmandu and local porters. In Langtang NP local porters constitute nearly two thirds of the total. Among all these visitors, the average annual number of people who could contribute directly to wood consumption (i. e., individual trekkers, their guides/porters, and local porters for group trekkers) and the average length of their stay were multiplied to evaluate their impact in the two park areas. The calculated total number to Sagarmatha NP was 24×10⁴ visitor·days and that to Langtang NP was 20×10⁴ visitor·days. A reduction in impacts to forests may be possible if the following two goals can be achieved: (1) reducing wood consumption by individual trekkers and their guides and porters at “hotels, ” and (2) reducing wood consumption by local porters along trails. Some specific measures to reduce wood consumption in the Nepal Himalaya are presented.