Exhibit 11.1

WESTERN GAS RESOURCES, INC.        COMPUTATION OF PER SHARE EARNINGS        DECEMBER 31, 2003

|                                                                                                                      |                                                                                 | Weighted Average Shares Of Common Stock Outstanding |  | Net Income |            | Earnings Per Share Of Common Stock
|--------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------- | --------------------------------------------------- |  | ---------- | ---------- | ----------------------------------
|Net income                                                                                                            |                                                                                 |                                                     |  | $          | 84,219,000 |                                   
|Weighted average shares of common stock outstanding                                                                   |                                                                                 | 33,206,114                                          |  |            |            |                                   
|Less preferred stock dividends:                                                                                       |                                                                                 |                                                     |  |            |            |                                   
|                                                                                                                      | Special dividend on redemption of $2.625 cumulative convertible preferred stock |                                                     |  |            |            | (45,420                           
|                                                                                                                      | $2.625 cumulative convertible preferred stock                                   |                                                     |  |            |            | (6,795,651                        
|                                                                                                                      |                                                                                 |                                                     |  |            |            |                                   
|                                                                                                                      |                                                                                 | 33,206,114                                          |  | $          | 77,377,929 |                                   
|                                                                                                                      |                                                                                 |                                                     |  |            |            |                                   
|Basic earnings per share of common stock                                                                              |                                                                                 |                                                     |  |            |            |                                   
|                                                                                                                      |                                                                                 |                                                     |  |            |            |                                   
|Assume exercise of common stock equivalents
(Anti-dilutive common stock equivalents are not used in this calculation) |                                                                                 | 4,141,096                                           |  |            | 6,841,071  |                                   
|                                                                                                                      |                                                                                 | 37,347,210                                          |  | $          | 84,219,000 |                                   
|                                                                                                                      |                                                                                 |                                                     |  |            |            |                                   
|Fully diluted earnings per share of common stock                                                                      |                                                                                 |                                                     |  |            |            |                                   
|                                                                                                                      |                                                                                 |                                                     |  |            |            |                                   



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