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 |                                                                                 | 66,412,228                                          |  |            |            |                                   
|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                        
|                                                    |                                                                                 |                                                     |  |            |            |                                   
|                                                    |                                                                                 | 66,412,228                                          |  | $          | 77,377,929 |                                   
|                                                    |                                                                                 |                                                     |  |            |            |                                   
|Basic earnings per share of common stock            |                                                                                 |                                                     |  |            |            |                                   
|                                                    |                                                                                 |                                                     |  |            |            |                                   
|Assume exercise of common stock equivalents         |                                                                                 | 8,282,192                                           |  |            | 6,841,071  |                                   
|                                                    | (Anti-dilutive common stock equivalents are not used
in this calculation)       |                                                     |  |            |            |                                   
|                                                    |                                                                                 | 74,694,420                                          |  | $          | 84,219,000 |                                   
|                                                    |                                                                                 |                                                     |  |            |            |                                   
|Fully diluted earnings per share of common stock    |                                                                                 |                                                     |  |            |            |                                   
|                                                    |                                                                                 |                                                     |  |            |            |                                   

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