<PAGE>
                                                                   EXHIBIT 11.1

                           ENERGY BIOSYSTEMS CORPORATION
                  BASIC AND DILUTED EARNINGS PER SHARE COMPUTATION
                           YEAR ENDED DECEMBER 31, 1995



WEIGHTED AVERAGE SHARES OUTSTANDING:

<TABLE>
<CAPTION>

    TOTAL                        # DAYS
   SHARES                      OUTSTANDING
--------------                -------------
<S>             <C>           <C>           <C> <C>
  9,988,409      x                        2   =    19,976,818
  9,988,409      x                       28   =   279,955,452
  9,999,404      x                        4   =    39,997,616
 10,000,604      x                        4   =    40,002,416
 10,040,604      x                       16   =   160,649,664
 10,041,604      x                        1   =    10,041,604
 10,046,604      x                       62   =   622,889,448
 10,228,645      x                       21   =   214,801,545
 10,233,645      x                       89   =   910,794,405
 10,235,645      x                        2   =    20,471,290
 10,237,645      x                        7   =    71,663,515
 10,242,640      x                       18   =   184,367,520
 10,249,640      x                       13   =   133,245,320
 10,258,241      x                        7   =    71,807,687
 10,270,241      x                        1   =    10,270,241
 10,293,241      x                        4   =    41,172,964
 10,368,241      x                        3   =    31,104,723
 10,370,749      x                       23   =   238,527,227
 10,512,618      x                        1   =    10,512,618
 10,513,388      x                        8   =    63,080,328
 10,514,288      x                        1   =    10,514,288
 10,514,788      x                        2   =    21,029,576
 10,516,788      x                        2   =    21,033,576
 10,524,188      x                       30   =   315,725,640
 10,524,268      x                       18   =   189,436,824
                                        ---     -------------
                                        365     3,733,072,305


                                                3,722,072,305 / 385 = 10,227,595
                                                                      ----------
                                                                      ----------
LOSS PER SHARE:
     Net Loss plus dividend accrual
     plus accretion of offering costs             ($9,713,069)   =         $0.95
--------------------------------                  -------------       ----------
        Weighted Avg. Shares                       10,227,595         ----------

</TABLE>

<PAGE>


                           ENERGY BIOSYSTEMS CORPORATION
                  BASIC AND DILUTED EARNINGS PER SHARE COMPUTATION
                           YEAR ENDED DECEMBER 31, 1996



WEIGHTED AVERAGE SHARES OUTSTANDING:

<TABLE>
<CAPTION>

    TOTAL                        # DAYS
   SHARES                      OUTSTANDING
--------------                -------------
<S>             <C>           <C>           <C> <C>
 10,584,268      x                       23   =   243,438,164
 11,107,568      x                       14   =   155,505,952
 11,139,268      x                       27   =   300,760,236
 11,140,768      x                        8   =    89,126,144
 11,142,868      x                       55   =   612,857,740
 11,301,975      x                       28   =   616,455,300
 11,302,025      x                       16   =   180,832,400
 11,303,525      x                        7   =    79,124,675
 11,309,295      x                        1   =    11,309,295
 11,309,355      x                        5   =    56,546,775
 11,310,855      x                        7   =    79,175,985
 11,311,955      x                        5   =    56,559,775
 11,316,955      x                        4   =    45,267,820
 44,318,210      x                       28   =   316,909,880
 11,320,010      x                        4   =    45,280,040
 11,320,210      x                       23   =   260,364,830
 11,325,210      x                       41   =   464,333,610
 11,326,210      x                        9   =   101,935,890
 11,490,770      x                       52   =   597,520,040
 11,497,135      x                        9   =   103,474,215
                                        ---     -------------
                                        386     4,116,778,466

                                                4,116,778,766 / 365 = 11,248,029
                                                                      ----------
                                                                      ----------
LOSS PER SHARE:

Net Loss plus dividend accrual
plus accretion of offering costs                  ($11,720,213)  =        ($1.04)
--------------------------------                  -------------       ----------
Weighted Avg. Shares                                11,248,029        ----------

</TABLE>

<PAGE>

                           ENERGY BIOSYSTEMS CORPORATION
                  BASIC AND DILUTED EARNINGS PER SHARE COMPUTATION
                           YEAR ENDED DECEMBER 31, 1997



WEIGHTED AVERAGE SHARES OUTSTANDING:

<TABLE>
<CAPTION>

    TOTAL                        # DAYS
   SHARES                      OUTSTANDING
--------------                -------------
<S>            <C>            <C>         <C> <C>
 11,497,135      x                      15  =     172,457,025
 11,502,135      x                       1  =      11,502,135
 11,502,235      x                       7  =      80,515,645
 11,502,395      x                      18  =     207,043,110
 11,505,395      x                       8  =      92,043,160
 11,506,053      x                      13  =     149,578,689
 11,507,163      x                       6  =      69,042,978
 11,605,377      x                      52  =     603,479,604
 11,724,758      x                      63  =     737,903,754
 11,763,593      x                      20  =     235,271,860
 11,764,343      x                      36  =     423,516,348
 11,765,343      x                       8  =      94,122,744
 11,777,924      x                      24  =     282,670,175
 11,778,204      x                       1  =      11,778,204
 11,780,704      x                      15  =     176,710,560
 11,896,470      x                       1  =      11,896,470
 11,896,670      x                       4  =      47,586,680
 11,899,670      x                       9  =     107,097,030
 11,935,951      x                       6  =      71,615,706
 12,201,434      x                       4  =      48,805,736
 12,218,434      x                      11  =     134,402,774
 12,251,434      x                      43  =     526,811,662
                                       ---      -------------
                                       365  =   4,295,852,050

                                                4,295,852,050 / 365 = 11,769,458
                                                                      ----------
                                                                      ----------

LOSS PER SHARE:

Net Loss plus dividend accrual
plus accretion of offering costs                ($12,849,466)  =         ($1.09)
-------------------------------                 -------------        ----------
      Weighted Avg. Shares                        11,769,458         ----------

</TABLE>